Gemstone Information

Compared to many, what I know about gemstones and rocks is limited.  What I do know, I owe to many people - my father the rockhound, Dr. Smith who taught me basic geology at Ohio State University, and the authors of too many rock and gemstone articles and books to mention.  What follows is a very basic summary of information about some common gemstones. I have included some of the common beliefs about gemstones and their uses where I can. 

I have loosely grouped rocks into categories but of course, there are so many that are only known by their trade names that it is difficult to keep them in strict categories and still have you find the one you want information about.  They are listed here in alpha order by category.  If you don't know your stone's category, you can scroll though to see if there is a description on this page.  If not, please contact me and I will be happy to send you information about your rock.

Each category is linked; the stones included in that category are listed after the link in parentheses.

Agates    ( Blue Lace Agate, Botswana Agate, Dendritic Agate, Fire Agate, Holly Blue Agate, Moss Agate, Plume Agate)

Alexandrite     Amazonite     Amber     Amethyst    ( Amethyst Quartz, Ametrine )

Andalusite     (Chiastolite)       Angelite     Apatite      Aragonite  

Aventurine   Azurite     Barite     Basic Terminology     Bloodstone    

Beryl    (Aquamarine, Bixbite, Emerald, Goshenite, Golden Beryl, Heliodor, Morganite)

Blue Quartz     Bronzite     Carnelian     Cat's Eye Quartz     Chalcedony

Charoite     Chrysanthemum Stone     Crysocolla     Chrysoprase     Citrine     Coral    

Crazy Horse Stone         Danburite

Diamond     Diopside     Dumortierite     Fluorite     Fuchsite     Garnet     Goldstone     Hawk's Eye    

Hematite      Herkimer Diamond     Howlite     Iolite     Jade   (Jadeite, Nephrite)

Jasper   (Desert Jasper, Leopard Jasper, Moukaite or Mookaite, Ocean Jasper, Red Jasper, Wild Horse Jasper)

Kunzite     Kyanite     Lapis Lazuli   

Larimar     Labradorite     Leopardite    Lepidolite      Malachite     Moldavite     Moonstone  

Muscovite         Obsidian   (Gold Sheen Obsidian, Mahogany Obsidian, Rainbow Obsidian, Snowflake Obsidian)

Onyx     Opal     Opalite     Pearl     Peridot     Pietersite 

 Prehnite     Pyrite     Prasiolite     Quantum Quattro Silica   

Quartz  (Druzy Quartz, Lemon Quartz, Lodalite, Purple Quartz, Rose Quartz, Rutilated Quartz, Smoky Quartz)

Red Creek Stone  

Rhodochrosite     Rhodonite   

Rhyolite      Sagenite (Sagenitic Quartz)   Sapphire/Ruby     Sardonyx     Seraphinite     Serpentine     Sodalite   

Sunstone    Tanzanite     Tiger's Eye     Topaz    

Tourmaline   (Achroite, Dravite, Indicolite or Indigolite, Rubelite, Siberite, Schorl, Verdilite, Watermelon)

Tourmalinated Quartz     Turquoise

Wavellite   Zircon

Some Basic Terminology

Rocks - rocks are any aggregate  of natural minerals found in the earth's crust.  While strictly speaking, gemstones are not rocks, I am the daughter of a rock hound, and grew up calling all of my pretty gemstones "rocks."

Stones - we use the term stones to denote any solid constituent of the earth's crust, however in the jewelry trade, stones means gemstones.  I'm also a gardener, and so I also use the term to describe the boulders in my garden!

Gemstones - this term is used to describe ornamental stones that can be and are used in jewelry or for carving ornamental objects.

Precious and semi-precious stones - there is no real difference between precious and semi-precious stones.  In the past, semi-precious was used to refer to softer stones that are used in jewelry making and for making ornamental objects.  The harder stones, corundum and diamond, were then referred to as precious stones.  If you like the rock and want to own and/or wear it, in my book it's precious.

Minerals - minerals are the natural, inorganic, solid constituents of the earth's crust.  Most minerals have a definitive crystal structure, but not all. 

Crystals - "A crystal is a uniform body with a geometric lattice.  The varying structures of the lattice are the causes of the varying physical properties of the crystals and therefore also of the minerals and gems."  (Schumann, 1977).  This is why you can have microcrystalline quartz (agate and jasper) and macrocrystalline quartz (amethyst and citrine) - the quartz forms different types of lattice in the crystal structure.

Carat - This term has been used to describe the weight of gemstones for centuries, however the meaning of the term has changed.  Originally, a carat was either the weight of a carob bean or the weight of a kaura seed.  In 1907, the metric carat was adopted, resulting in all carats weighing the same amount - 200 mg or 0.2g.  Carats are divided into "points"  of 100, up to two decimals.  So, you might see a stone that weighs 4.25 carats, for example.

Karat - a measure of the amount of pure gold in an object made of gold.  24 karat indicates pure gold, so to determine the amount of actual gold in your jewelry, divide the karat indicated by 24.  This makes 18 karat gold 75% gold, 14 karat gold 58.33% gold, and 10 karat 41.67% gold.  In the U.S., any gold fineness under 10 karat may NOT be labeled as gold.   24 karat gold is soft, therefore other harder metals are added (alloyed) to the gold to make it harder and so that the item will retain its shape and wear longer.

Refractive Index - this index is used to help identify gemstones.  Many gemstones appear similar to the untrained eye.  All gemstones have refraction - the effect you see when light moves from one medium to another.  You can see this effect if you place a stick into water - the stick appears to bend where it enters the water; it doesn't, but it looks as though it does.  Light does this same thing when it enters a gemstone crystal.  The different lattices in the crystals will cause the light to bend in different ways.  This is called the gemstone's refractive index.  Some gemstones are singly refractive (one ray of light comes out of the bending of the light ray), and some gemstones are doubly refractive (two rays of light come out of the bending of the light ray). 

Dispersion - The white light coming into a gemstone is not only bent, it is fanned out into spectral colors (the rainbow).  Individual colors in the spectrum have different wave lengths.  This division of the white light into colors of the rainbow is called dispersion.  This dispersion is also referred to as the play of color in a gemstone.  This dispersion is particularly important in valuing some stones such as diamonds, which are highly dispersive, and opals, which rely on the dispersion for their play of color thoughout the stone.  Generally speaking, only colorless gemstones have high dispersion.

Transparency - Inclusions of foreign matter, bubbles, fissures, etc. in the interior of a gemstone effect the transparency of the rock.  Basically, anything that blocks the light from moving through the stone will effect the transparency.  If the light is weakened by the lattice of the crystal or by inclusions, the stone is said to be transluscent.  If the light is also effected by the absorption in the crystal, where the rays of light are repeatedly refracted by the many tiny crystal faces until they are completely absorbed, the rock will be opaque.  Generally speaking, the more transparent a gemstone is, the more valuable the rock will be.

Luster - not all light moves through the gemstone; some light is reflected back off the surface of the rock.  This reflective property is dependent on the nature of the surface of the rock and the refractive index, but not on the color of the rock.  The most desired luster is adamantine (highly reflective like a diamond), the most common is vitreous (glassy).  Luster can also be described as fatty, metallic, pearly, silky and waxy.  If a rock has no luster, it is called dull.

Organic Gemstones - Although stones are generally inorganic, there are gemstones that are organic in nature.  These include pearls, amber, coral and some fossils among others.

Mohs scale of hardness - a generally agreed upon scale that rates the hardness of stones when compared to other stones.  Viennese mineralogist Friedrich Mohs came up with this scratch relative hardness test .  Using this scale, minerals of the same hardness can not scratch each other, but can scratch softer minerals.  In this scale, minerals that are rated 1 or 2 are classified as soft, minerals that are rated 3 to 6 are medium, and over 6 are classified as hard.  Any jewelry made with gemstones under 7 should be treated with care and the wearer should avoid contact with any item that might scratch the gemstone.  People who actually cut gemstones do not use this scale, rather they use the Rosiwal scale which indicates actual hardness.

Inclusions - Many crystals solidify around other "things" such as other crystals, bugs, air bubbles, plants, fissures in the crystal, etc.  When crystals are found that have these types of things in them they are termed "included" crystals.  We rock hounds talk about inclusions to excess!  Some of them are truly fascinating and beautiful.

Brecciated - brecciated literally means to break into pieces.  In rocks, brecciated means that the original minerals or crystals have been folded, stressed, fractured, etc. then reformed into a stone by some natural process, usually reforming with quartz.

Pleochroism - a phenomenon where the gemstone displays different colors, depending on the angle at which the stone is viewed.  Tanzanite, for example, can appear blue, violet or red, depending on the angle at which it is viewed.  When only two colors are visible, the stone is sometimes referred to as dichroic rather than pleochroic. Some refer to stones that display three colors as trichroic, rather than pleochroic.

Asterism - a phenomenon where fibrous inclusions in the stone create a star-like effect on the top of the stone when cut.  The best known example of this effect is the star sapphire, but many stones can display this effect.

Chatoyant - means having a changing luster.  In many gemstones, the luster on the surface of the stone changes as you rotate the stone in a light source.  It often resembles the effect of a cat's eye.  Tiger's Eye, Hawk's Eye, Cat's Eye Quartz, etc. at all examples of chatoyant stones.

Relative and Absolute Hardness of Minerals (from W. Schumann)

Scratch Hardness
(Mohs scale)

Mineral Used for
Comparison

Simple Hardness Test Cutting Hardness
(Rosiwal scale)
1 Talc Can be easily scratched with fingernail 0.03
2 Gypsum Can be scratched with fingernail 1.25
3 Calcite can be scratched with copper coin 4.5
4 Fluorite Easily scratched with a knife 5.0
5 Apatite Can be scratched with a knife 6.5
6 Orthoclase Can be scratched with a steel file 37
7 Quartz Scratches window glass 120
8 Topaz Scratches quartz 175
9 Corundum (sapphire) Scratches topaz 1000
10 Diamond   140,000

Naming of Gemstones

Gemstones are sometimes known by multiple names.  This is confusing both to the buyer and to those of us who collect and sell gemstones.  Because gems have been sought after and collected by mankind for centuries, original names tended to focus on the characteristics of the stone or the place where the stone was found.  For example the Greek word prase means green - so, many green stones had the term prase in the name.  Some were also named for their "powers" such as amethyst which is said to prevent drunkeness.  Agates were named after a river in Sicily where they were found.  It was only much later that we began to understand the science behind these beautiful rocks and assign scientific names.  The modern principle of naming rocks (and new ones are still being found) is to devise the name based on the Latin or Greek for a special characteristic of the stone, the place of occurence, or after a person.  However, this still leads to much confusion. 

In addition to the scientific name, the jewelry trade often uses completely different names to market stones.  A recent example of this is prasiolite (leek green macrocrystalline quartz which is obtained by heating amethyst) is often marketed as green amethyst.  Because the general public doesn't know what prasiolite means or is, in order to increase sales a new name has been made up.  This is also true of Tanzanite (blue zoisite) and Tsavorite (green grossular garnet).  In order to increase the sales of the stones, new names were given.

In the gemstone information below, I try to give you both the scientific names and the common names of stones, but because marketers are always coming up with new ways to sell stones, I probably have not included all of them.  If you see a gemstone name and can't find it below, just email me and I'll research the stone for you.  I love to learn more about these rocks every chance I get.

The stones below are loosely grouped by type, however, I've also attempted to place them under a heading that you will know, and therefore be able to locate in the following paragraphs.  

The information contained below is by no means complete - I have tried to include all the rocks that I have used in making jewelry.  Any mistakes are my own.

Agates

There are over 700 known named agates.  This is mostly a way to market these rocks with somewhat different colors, inclusions, etc.  Below are a few of  the most common named agates that you will find.

Blue Lace Agate

Blue lace agate is one of the most popular, and rather rare forms of agate.  The natural blue lace agate has soft blue primary coloring with with paler blue to white bands running through the stones.  Blue lace agate - and all agates really - are in the group of microcrystalline quartz known as chalcedony, which is known for its vitreous or waxy luster.  Chalcedony and agate ranges from 6.5 to 7.5 on the Mohs scale of hardness, making them durable stones to wear every day.

Newer techniques allow for the natural agates to be dyed, making them some fairly unusual colors Mother Nature never intended.  However, some of the dyed colors are quite pretty - the blue dyed agates however, are no match for the lovely natural color of blue lace agate. 

Blue lace agate is supposed to be calming, uplifting and to encourage peace.  Some people wear or carry blue lace agate for peace and happiness, and believe that if you hold the stone in your hand, it will help you de-stress. 

Botswana Agate

Botswana agate is a chalcedony.  All chalcedony or agates belong to the microcrystalline group of quartz and have a range of 6.5 to 7.5 on the Mohs scale of hardness.  Botswana agates are known for their concentric rings that sometimes resemble an eye.  Most Botswana agates are shades of gray, black, and brown, with cream or white rings.  However, some Botswana agate near the surface of the ground has bleached and become shades of pink, peach and soft orange with white and cream rings.  These bleached Botswana agates are the most rare. 

Botswana agate is believed to ward off the evil eye in many cultures.  Others believe that Botswana (a.k.a. Eye Agate) will help you become more confident and protect you from being hurt.  In some cultures, Botswana agate is believed to enhance sexual energy and physical stamina.

Dendritic Agate

Strictly speaking, dendritic agate is not an agate (in scientific terms) as it lacks the rings common to agates.  However, dendritic agate is a chalcedony, a form of microcrystalline quartz known for its waxy or vitreous luster.  All agate or chalcedony belongs to the microcrystalline quartz family and all will have a range of 6.5 to 7.5 on the Mohs hardness scale. 

Dendritic agate is a clear to transluscent white chalcedony with branch or fern-like inclusions of iron oxide or manganese oxide. Because these stones were at one time shipped from India to Europe through the Arabian port of Mocha, in some cultures this stone is called Mocha Stone.  Dendritic agate is also sometimes called Tree Agate, probably because some of the inclusions look like trees or plants.

Dendritic agate has been found in Brazil, Madagascar, the USA, Mexico and Khazakstan. 

Dendritic agate is said to hellp you connect with nature and gain emotional balance. Others claim that dendritic agate can promote wealth.

Fire Agate

Fire agate is a variety of quartz containing inclusions of goethite or limonite, producing an irridescent effect or "fire."  Like all agates, fire agate is a microcrystalline form of quartz that is within the group called chalcedony.  The hardness of fire agate ranges from 6.5 to 7.5 on the Mohs hardness scale.

Fire agate is believed to have a deep calming energy that brings secruity and safety.  In addition, fire agate is believed to help heal stomach ailments, overcome addictions, and reduce night sweats.

Holly Blue Agate

This agate isn't actually blue - it's dark lavender! But, It comes from the Holley Mountain region of Oregon and is found in seams within basalt.  Holly blue agate tends to be highly fractured and as a result is highly included, color banded and externally pitted making it difficult to cut good cabs.  The site has been closed for some time and the cost of holly blue agate has gone up exponentially as a result.  When you can find good cabochons, it is a gorgeous stone!

Moss Agate

Moss agate is a chalcedony that can be clear to transluscent white or cream  displaying brown to green inclusions that resemble moss.  These "moss" inclusions are hornblende.  Technically speaking, moss agate is not an agate as it lacks the banding common to all agates, however it is a microcrystalline quartz.  When there are numerous hornblende inclusions, moss agate is sometimes called moss jasper in the trade; however, it is not a jasper.  Moss agate has a 6.5 to  7 on the Mohs hardness scale.

Most moss agate in the trade comes from India, however it can be found in the U.S. A. in Colorado, Michigan, Montana, Oregon, Utah, Washington, and Wyoming.

Some believe that moss agate helps to balance emotional energy by helping you let go of anger and bitterness.  Moss agate is also said to help you with concentration, persistence and endurance.

Plume Agate

Plume agate primarily comes from the eastern border of Oregon/western border of Idaho and is found in vertical seams of basalt matrix.  It comes in a variety of colors, and good "plumes" are hard to locate.  The plumes can be caused by various inclusions and minerals.  Plume agate comes in a variety of colors.

Alexandrite

Alexandrite belongs to the chrysoberyl family and has a Mohs hardness rating of 8.5.

Alexandrite was first found in Russa and has since been found in Brazil and Madagascar.  The Russian material is still considered the best quality Alexandrite.  Alexandrite is a phenomenon gemstone that changes color in different light sources - from red in incandescent light to green in natural bright light.  Because of the rarity of the stone, it has been grown in laboratories for many years.  Good quality lab grown Alexandrite displays 100% color change, unlike much of the natural Alexandrite that is mined, which can have little to moderate color change.

Some believe that Alexandrite stimulates pleasure and love.  It is also frequently used as a lucky stone - well, if you can afford a real Alexandrite, you are indeed lucky!

Amazonite

Amazonite is a blue-green variety of feldspar named after the Amazon River where it was first found.  Current sources include Russia, Brazil, China, India and Colorado in the U.S.  The Russian amazonite tends to be darker and more green in color than some of the other deposits, which are a softer color and more aqua in tone.   

Technically, amazonite is a microcline feldspar; the color comes from lead impurities in tihe crystals.

Amazonite has a 6.5 rating on the Mohs hardness scale.

Amazonite is said to promote kindness and practicality.

Amber

Amber is the fossilized sap from prehistoric pine trees (Pinus succinifera) and may include bugs, pieces of plants, bubbles and even pyrite.  Most of these types of inclusions add value to the amber, although bubbles are often removed by boiling the amber.  Amber comes in a variety of colors including a yellow golden hue, milky white, red-orange, green and black.  Amber is very light weight, making it easier to use in large pieces for jewelry.  The hardness of amber is around 2 on the Mohs hardness scale, so becareful with this gemstone as it is relatively fragile.  Amber is an organic gemstone.

True amber is found in Europe, with the largest deposits in Poland and around the Baltic Sea.  However, there is a similar fossilized sap found in South America referred to as copal.  Care should be taken when purchasing any item labeled as copal as this name is also used for imitation amber made from resins by some manufacturers.  There is also a great deal of imitation amber on the market made from resins that is sometimes sold as amber.  Reconstituted amber (pieces pressed together) is also on the market.  Buyer beware!

Amber has a long history of use by healers for headaches, heart problems, arthritis, and a variety of other ailments.  Some believe that amber promotes luck and success.  Others believe that amber will help you have a happier disposition.

Amethyst

Macrocrystalline quartz comes in many colors.  When macrocrystalline quartz is some shade of purple, it is called amethyst.  Amethyst is a 7 on the Mohs hardness scale. The word amethyst comes from the Greek meaining "without drunkenness." 

Amethyst is often heat treated to improve color and, often, to change the color to leek green (prasiolite) or yellow (citrine).  Some amethysts will lose their purple color when exposed to daylight.  The purple color can then only be restored through x-ray radiation - so protect your amethyst from light when not being worn.

Amethyst has been used to help resolve insomnia by placing an amethyst under your pillow to bring about pleasant dreams.  Amethyst has also been used to help with breathing problems.

Amethyst Quartz

Amethyst quartz is amethyst that is banded or layered with milky quartz.  It is still a macrocrystalline quartz; it just displays another type of quartz with the amethyst.  The hardness is still 7 on the Mohs scale.

Ametrine

Ametrine is a macrocrystalline quartz where amethyst and citrine (purple and yellow quartz) occur naturally in the same crystal.  This is a natural color zoning that cannot be duplicated in a lab.  The highest quality ametrines are those cut to display a 50/50 split between the amethyst and citrine coloring.  Ametrine is also a 7 on the Mohs hardness scale.

Because there is only one mine where this unique combination of quartz colors has been found, ametrine is considered rare.  The mine is located in Brazil and is producing only small amounts of rough material.

Ametrine is thought to be helpful in overcoming depression and in achieving inner peace and tranquility.

Andalusite

Andalusite is a pleochroic gemstone (displaying three or more colors depending on the angle at which the stone is viewed) originally found in the Andalusia region of Spain in 1798.  Although most pleochroic gems are cut to display the best of the colors (for example Tanzanite is cut to display the blue color whenever possible), the opposite is true of andalusite.  Andalusite is cut to display all the colors in the gemstone.  Current deposits producing andalusite include Brazil and Sri Lanka, although it is also found in Chile, Russia, Spain, Canada and the U.S.  Because the stone has such strong pleochroism and is relatively rare, it is considered a collector's gemstone.  Andalusite is a 7.5 on the Mohs hardness scale.

Lore has it that fighters are attracted to andalusite, however once they obtain an andalusite stone, they become wiser and give up fighting. 

Chiastolite

Chiastolite is the brown variety of andalusite which often displays carbon inclusions that resembles a cross.  The name chiastolite derives from the Greek chiastos, meaning "cross marked."  This type of andalusite is softer and has a Mohs hardness rating of 5.5.  Although sometimes referred to as the Cross Stone, that term is more appropriately used for staurolite.

Chiastolite was often worn as an amulet in ancient times.  In modern times, chiastolite is believed to dispel negative thought and energy.

Angelite (Anhydrite)

Anhydrite comes in clear, white, blue and violet-red.  Most is not facetable quality.  Some of the blue anhydrite, while not of a quality for faceting, can be waxed so that it will take a polish and therefore can be cut into cabochons and beads.   These blue stones are then referred to as angelite.  The blue is generally a soft grayish -blue.   Angelite is a soft stone - only 3.5 on the Mohs hardness scale and should not be used in rings as the stone is likely to chip or crack with hard wear.   Care should also be taken when cleaning angelite so as not to remove the wax.  Clean angelite with a soft damp cloth.

Angelite is believed to promote compassion and understanding and to facilitate contact with angels.  Angelite is also believed to help with weight control.

Apatite

Apatite is considered a collector's gem as good quality deposits of any color are rare.  Apatite tends to be heavily included and cracked, making it dificult to obtain good quality cut stones and beads.  Apatite comes in yellow, blue, green, blue-green and a bright peacock blue.  Apatite is a relatively soft stone with a rating of 5 on the Mohs hardness scale.  Although it can be worn in all types of jewelry, in rings, apatite should not be worn on a daily basis as the stone may chip or crack if bumped against a hard surface.

Yellow apatite is considered a learning stone used during meditation to clarify your life's purpose.

Blue, green and blue-green apatite is considered an inspirational stone used to develop spiritual attunement.

Apatite is believed to heal bones, relieve arthritis pain and to reduce hypertension.

Aquamarine - See Beryl

Aragonite

Aragonite varies in color and can be white, yellow, reddish, or brown.  Aragonite is formed from calcium carbonate deposits around hot springs or in stalactites in caves.  Also known as Tufa Stone, and in some forms as Travertine, aragonite is relatively soft with a 3.5 to 4 rating on the Mohs hardness scale.

Aragonite is considered very useful during stressful times.  Some believe that aragonite can help with calcium absorption and can reduce muscle spasms at night.

Aventurine

Aventurine is a crypto-crystalline quartz colored by either fuchsite (green mica) inlcusions or by iron mica inclusions, so aventurine is either shades of green or rusty red.  Do not confuse quartz aventurine with feldspar aventurine - more commonly called sunstone - which obtains its color from hematite or goethite inclusions.  Quartz aventurine is a 7 on the Mohs scale of hardness.

Green aventurine is believed to bring luck and improve chances.  Green aventurine is also believed to increase perception and creative insight.

Yellow aventurine (really pale red aventurine) is believed to balance emotions and male/female energies.

Red to orange aventurine is believed to assist in creativity, and to help you see possibilites in new opportunities.

Azurite

Azurite was named for its azure blue color and it is found in copper deposits, frequently with malachite.  Azurite and malachite can actually be found in the same stone and the combination makes a very interesting stone for use in jewelry.  Azurite can also be found as spherical aggregate deposits.  At one time, this stone was used as pigment in azure blue paint.  Azurite is relatively soft - 3.5 to 4 on the Mohs hardness scale - so it should be used in necklaces and earrings rather than in rings.  Azurite is usually stabalized by waxing or coating with a resin to help the stone retain its color and to help avoid damaging the stone. 

Azurite is believed to increase communication skills, intuition and creativity.  Some believe that azurite can help heal the liver and can aid in detoxification.

Barite

Barite (also known as Baryte) can be colorless, brown, yellow, red, white, light blue or green.  It forms either a tabular crystal or rosette crystal.  The tabular crystals are sometimes faceted, but I like the rosette crystals - they're just pretty.  Barite is considered a collector's gemstone.  Barite is soft; only 3 on the Mohs hardness scale.

Barite is believed to assist with reaching higher realms during meditation and to cleanse your energy.  Some believe that barite can assist in balancing the brain's chemistry.

Bloodstone (Heliotrope)

Bloodstone is a dark green form of chalcedony or microcrystalline quartz that often has red spots or streaks.  Because of these red colorations, the stone is often called bloodstone, rather than the more accurate name, heliotrope.  Bloodstone/heliotrope can also include white and other colors of quartz.  Bloodstone is a 6.5 to 7 on the Mohs hardness scale.  Bloodstone or heliotrope is mined in India, Brazil, China, Australia and the U.S.

During the Middle Ages, the red colorations were thought to be the blood of Christ, and so special powers were attributed to heliotrope, along with the name bloodstone.

In some cultures, bloodstone is believed to aid in stopping bleeding.  In other cultures, bloodstone is believed to bring change.  Some also believe that bloodstone can aid circulation.

Beryl

Beryl is beryllium aluminum silicate.  Beryl comes in many colors including green, blue, gold, yellow-green, blue-green, pink and colorless.  Each color variety has a special name used in the jewelry and gemstone trade.  All beryl is rated from 7.5 to 8 on the Mohs hardness scale.  Beryl is generally cut into octagon or "emerald" cuts as the crystal structure lends itself well to this type of faceting.  Opaque beryl can have a cat's eye effect or asterism.  Beryl is often heated to improve the color.  Specific beryl trade names are:

Green beryl - emerald

Blue to blue-green beryl - aquamarine

Red beryl - bixbite

Pink beryl - Morganite

Gold beryl - golden beryl

Yellow beryl - heliodor

Colorless beryl - goshenite

Aquamarine

Aquamarine is the blue to blue-green color of beryl and it is colored by iron replacing some of the aluminum in the beryl crystals in a certain valance.  Dark sky blue is the most valuable color in this group.  Aquamarine is found on every continent and large crystals are common, although the best color is rare.  Care should be taken when purchasing aquamarine as lab grown blue spinels are sometimes sold as aquamarines. 

Aquamarine was a talisman for sailors in ancient times, because it is the color of the sea.  In modern times, aquamarine is considered a good stone to assist with meditation.  Some also believe that aquamarine can assist with the reduction of fluid retention and can help heal throat problems.

Bixbite

Bixbite isn't often called bixbite anymore; many now refer to this color of beryl as red beryl.  The change came about because there is another mineral with a similar name and it got confusing.  But, I've always know this stone as bixbite and I like the name.  It was named after Maynard Bixby of Utah, where it was first found in the Wah Wah Mountains.  It has also been found in New Mexico, but all sources are very limited and these stones tend to be very, very small.  And expensive!

Bixbite can be orange-red, red, or violet-red.  The most valuable color is a dark pinkish-red.  This beryl is colored by the presence of manganese.  Bixbite is sometimes confused with pezzottaite, which appears similar, but has a different crystal structure. 

Bixbite is thought to relieve depression and to provide energy.  Some also believe that bixbite aids in relationships by creating harmony.

Emerald

Emerald is the green form of beryl, and is considered the most valuable of all the beryl colors.  The color can be pale green to dark "emerald" green.  These green beryls are colored by chromium and sometimes vanadium.  Only the finest stones are transparent; most are heavily included with bubbles, cracks, and foreign crystals causing them to appear cloudy.  Included and/or cloudy dark green stones are considered more valuable than pale green clean stones.  The most famous emeralds come from Columbia; significant sources are also found in Brazil.

The emerald is thought to preserve love and is a symbol of hope.  It is also considered by some to bring the wearer wisdom and reason. Some also believe that the emerald can help heal the heart and diseases of the eye.

Goshenite

Goshenite is the trade name for the pure beryllium aluminum silicate crystals - the colorless beryl which has no "contaminants".  This colorless variety of beryl is named after the town in Massachusetts where is was first found - Goshen - but is now found in Columbia, Northern Europe and the Himalayan regions of Asia.

Goshenite is thought to help actions and thoughts become true to your deepest desires.  At one time, Goshenite was used as a divining tool in ancient Ireland.

Golden Beryl

Golden beryl is colored by iron when the beryl is in a certain valance state (in others it would be blue from the iron).  Golden beryl is usually not treated to improve color as the color is so saturated when the crystals are mined that this is not necessary.  Most golden beryl is currently from Brazil and Madagascar.

Golden beryl is said to clear the mind and to promote genuine love and affection when worn as a ring.  Some also believe that golden beryl instills purity in all aspects of life.

Heliodor

Under certain valance, iron can replace some of the aluminum in beryl and produce a yellow beryl.  Although some refer to golden beryl and heliodor as the same, they are technically different beryls with heliodor having a true yellow color, and golden beryl having a true golden color (similar to the distinction between golden quartz and citrine).  The name heliodor comes from the Greek and means gift from the sun. 

Heliodor is said to improve mental clarity and to focus your will.  It is also believed to cleanse the body of toxins.

Morganite

Morganite is the pink member of the beryl family, colored by manganese.  Morganite can be soft pink, violet-pink, or pale violet.  Morganite was named after J. P. Morgan by Kunz, (the noted gemologist), as Morgan was an avid gem collector and friend of Kunz.  With morganite, color is the most important factor in determining value, however size is also very important as the larger the crystal, the darker the color is likely to be.

Morganite is thought to attract and keep love; it promotes abundance of the heart.  Some also believe that Morganite aids in the treatment of asthma, impotence and lung diseases.

Blue Quartz

Bue quartz, also known as siderite, is a coarse grained quartz aggregate that has crocidolite fiber inclusions that cause the opaque blue color.  Blue quartz is a 6.5 to 7 on the Mohs scale of hardness.

Blue quartz is thought to sooth and relieve stress.

Bronzite

Bronzite is technically called enstatite. Enstatite comes in brown, brown-green, gray and yellow.  The brown-green variety has a metallic sheen and is often referred to as bronzite.  The coloring of bronzite is due to a high iron content in the enstatite.  Bronzite and enstatite belong to the pyroxene family of minerals.  Bronzite is a 5.5 on the Mohs hardness scale.    Bronzite is found in South Africa, India and Burma (Myanmar).

Bronzite is used to promote harmony and self-confidence.  Some believe that bronzite can aid self-esteem.  In some cultures, bronzite is believed to ward off curses and ill wishes.

Carnelian

Carnelian (also sometimes spelled cornelian or kornelian as it was named ater the Kornel cherry color) is a chalcedony in the microcrystalline quartz family.  Color can range from a pale red to brown-red to orange.  The best quality carnelian is dark rust red.  Much of the carnelian on the market today is a pale chalcedony that has been dyed to obtain the rust-red color.  As with all chalcedony and quartz, carnelian ranges from 6.5 to 7.5 on the Mohs scale of hardness.

Banded carnelian color chalcedony is often referred to as sardonyx, rather than agate (the usual name for banded chalcedony).  When the plain or banded carnelian is more brown than red, it is often referred to as sard instead of carnelian.

In ancient times, carnelian was used as a talisman against idiocy and depression.  In modern times, carnelian is believed to provide energy and guard against poverty.

Cat's Eye Quartz

Cat's eye quartz is one of a group of quartz that have fibrous hornblende inclusions that, when the stone is cut as a cabochon, display chatoyancy ( a phenomenon that gives this quartz its name as it is said to look like a cat's eye).  Cat's eye quartz can be clear, white, gray green, yellow and brown to reddish-brown.  As with other quartz, cat's eye quartz is a 6.5 to 7 on the Mohs hardness scale.

Cat's eye quartz is sometimes confused with chrysoberyl cat's eye.  Since both stones display chatoyancy and are easily confused, cat's eye quartz should always be listed with the quartz label.  The chrysoberyl variety can be listed as cat's eye without any qualifier.

Chalcedony

Chacedony is a group of microcrystalline quartz that is found in a wide range of colors including blue, lavender, white, cream, gray, yellow, green, pink and brown.  When found with color bands, chalcedony is called agate.  In the jewelry trade, the word chalcedony is used to describe the blue, white and gray varieties of microcrystalline quartz.  Because it is porous, the white and gray varieties of chalcedony are often dyed other colors.  Even the natural blue chalcedony is often dyed a better, or darker, shade of blue.  The natural dark sky blue color is considered the most valuable of the blue chalcedonies.  Green chalcedony, better known as chrysoprase, is the most valuable of all the chalcedony family.  Chalcedony is a 6.5 to 7 on the Mohs hardness scale.

It is believed that chalcedony nurtures and promotes brotherhood and good will.  It is sometimes used to assist with telepathy.  Some believe that chalcedony can be used to cleanse wounds, and that it increases physical energy.

Charoite

Charoite is found only in Aldan, Russia along the Chary River.  It is formed from an alteration  of limestone caused by the close presence of an alkali-rich nephline syenite intrusion.  The resulting rock is a gorgeous stone that ranges from lavender to violet to dark purple with white, gray and black veining.  The interlocking crystals of the stone seem to create a swirling pattern in the stones, which are sometimes chatoyant (having a cat's eye effect).  Charoite has a hardness of 5-6 on the Mohs hardness scale.

Russians first discovered charoite in 1947, but it was not known here in the U.S. until 1978.

Some believe that placing a charoite beneath your pillow will calm your distrubed sleep and alleviate fears.  In combination with amethyst, charoite will be especially helpful in releasing these fears.

Chrysanthemum Stone

Chrysanthemum stone is named for its unique patterns embedded in the stone that resemble flowering chrysanthemums.  Chrysanthemum stone is comprised of dolomite, gypsum-bearing clay, limestone or porphyry with lath-like crystals of andalusite, celestite, feldspar, or calcite which are grouped into a pattern resembling blooming autumnal  chrysanthemum flowers.  Chrysanthemum stone is rated 4.5 on the Mohs hardness scale.

Chrysanthemum stone is said to help you find your purpose in life and give you the courage to follow your dreams.

Chrysocolla

Chrysocolla is blue to green and is often a vivid turquoise color with green streaks or swirls.  Chrysocolla is sometimes found intergrown with quartz, turquoise, or malachite, or some combination of these stones.  When chrysocolla, turquoise and malachite are all found in one rock, it is called eilat stone.  Alone, chrysocolla is soft - only 2 to 4 on the Mohs hardness scale; therefore chrysocolla is often stabilized with a wax on the surface to help protect this soft stone.  This does not decrease the value of the stone, but be careful as some sellers will compress pieces of the stone together with a resin and call it "stabalized" chrysocolla. 

Chrysocolla can be found in Chile, the Ural Mountains of Russia, Nevada and Arizona in the U.S., Mexico and Zaire. 

Chrysocolla is said to promote level headedness, clarity of thought and a cool attitude during turbulence.  It can be used to decrease nervousness and irritability.  Some believe that chrysocolla can assist with curing infections and reducing fevers.

Chrysoprase

Chrysoprase is the green color of chalcedony and is the most valuable of all the chalcedony group of quartz.  This microcrystalline quartz is colored by nickel and the quartz fibers have a radial structure, which is different than most of the chalcedony group.  Most of the chrysoprase - and the best color - comes from Queensland, Australia.  A lemon yellow form of chrysoprase is often seen on the market as citron or lemon chrysoprase.  It is less valuable and more opaque than the true green form of chrysoprase, but is a lovely stone none the less.  Chrysoprase is 6.5 to 7 on the Mohs hardness scale.

Chrysoprase is said to bring hope and joy to those who wear it and to help clarify problems.  Some believe that holding a chrysoprase over a wound will speed the healing.  It is also said that chrysoprase should only be set in silver when used in jewelry (however, I have yet to find out why).

Citrine

Citrine is the light yellow to golden brown variety of macrocrystalline quartz.  Natural citrines tend to be pale yellow, while the heat treated stones tend to have a reddish tone to the yellow color.  Natural citrine is actually fairly rare.  Most citrine on the market is amethyst or smoky quartz that has been heat treated to make it citrine colored.  As with many heat treated stones, you should keep your citrine in a dark place when not wearing it so that it will not lose color.  Chemicals can also cause the stone to lose some of its color.

The best known source of citrine is Brazil, however it is also found in the U.S., Spain, Russia, France and Scotland.  Like all quartz, citrine is a 6.5 to 7 on the Mohs hardness scale.

Keeping a citrine in a cash register is said to increase sales.  Citrine is also used to increase self-esteem and promote clarity of thought.  Some believe that citrine can aid digestion and relieve depression.

Coral

Coral is one of the organic gemstones and comes from the calcite deposits made by polyps in the ocean.  Noble red is considered the most valuable of all the corals, but coral comes in a variety of colors, including salmon pink, white, yellow, blue and black.  Much of the coral on the market is actually dyed to enhance or provide color and numerous imitations of coral can be found so be very careful when purchasing coral.  Coral has a Mohs hardness rating of 3 to 4.

Coral is harvested in the Mediterranean Sea, off the coast of Australia, the South Pacific and the coastal areas of Japan and Africa. 

Coral is believed to prevent ill fortune and offer protection from skin disease when worn as a necklace. Coral is also considered a good aid for meditation or visualization.  Some believe that dark red coral will stimulate the bloodstream.  Pink corals are said to restore harmony and aid in relieving depression.

Crazy Horse Stone

Crazy horse stone is a mottled limestone mined in China.  It is a soft stone, only 3 on th Mohs scale of hardness.  Because it is such a soft stone, crazy horse stone is always treated with a resin to protect the stone.  This is the same process used on other soft stones such as turquoise or chrysocolla.  The stone's softness also makes it difficult to polish.  For this reason, crazy horse stone usually has a matte polish.  Crazy horse stone gets its name from the mottling that resembles the marking on a pinto horse - but in colors not found on any animal.  The stone tends to be gray to pink-gray, with dark rose red or burgundy "pinto" spots.  There may also be a little to quite a lot of black in the stone.

Crazy horse stone is often confused with wild horse jasper that is mined in the Wild Horse Canyon mine in Oregon - Idaho.  Wild horse  jasper is a member of the quartz family and is much harder than crazy horse stone; a 6.5 to 7.5 on the Mohs scale.  Wild horse jasper will take a high polish and can be used in more types of jewelry as it will not break as easily as crazy horse stone.  Wild horse jasper is also known as picture jasper or wild horse picture jasper.  It comes in greens, golds, browns and other earthy tones. 

Crazy horse stone is also often confused with wild horse stone which is a magnesite ( a white soft stone) that often comes with veining that is a purple hued brown or a rosy brown.  It is mined in the Gila Wilderness Area of Arizona. 

Danburite

Danburite is a collectors' gemstone first found in Danbury, Connecticut and is calcium boric silicate.  Danburite can be colorless, yellow or pink.  Danburite is a 7 on the Mohs hardness scale.  It can currently be found in Mexico, Russia, Madagascar, Bolivia, Burma (Myanmar), and Japan.

Danburite is thought to help the wearer leave the past behind.  It is also believed to relieve stress and worry.  Some believe that danburite can aid with restful sleep.

Diamond

The diamond is the hardest of all gemstones - its name comes from the Greek word for unconquerable.  There are actually four different types of diamonds, however this difference is only of importance to those who are cutting the stones.  Diamonds come in all colors, but most are colorless (the most valuable), yellow, brown, blue, reddish and black.  Currently, many diamonds are irradiated to give them color or to improve color.  Although diamonds are rated 10 on the Mohs hardness scale, they are actually 140 times harder than corundum (sapphire) which is rated a 9 on the Mohs hardness scale.

Diamonds are one of the most commonly occuring gemstones on earth, however good quality diamonds are relatively rare.  Diamonds are a controlled commodity, which increases their price beyond what their common occurence would otherwise indicate.

Diamonds are said to be a symbol of innocence and constancy, hence their common use as an engagement ring stone.

Diopside

Diopside is a collectors' gemstone in the pyroxene group of minerals.  Diopside is light to dark green, bottle green (also known as chrome diopside), colorless and black.  Some diopsides display chatoyancy and are termed diopside cat's eye.  Other diopsides can display an asterism and are called star diopside.  Diopside ranges from 5 to 6 on the Mohs hardness scale.  A rare violet diopside is found in Piemont, Italy and is known as violane.

Black diopside is thought to help the wearer connect with the earth.  Green diopside is thought to provide balance and  healing.  Some believe that diopside can be used to aid in healing after surgery or trauma.

Dumortierite

Dumortierite is a collectors' gemstone that is rarely found as a crystal, however fibrous aggregates are more common.  Dumortierite is blue, violet-blue or reddish-brown.  Dumortierite is a 7 on the Mohs hardness scale and is made up of aluminum borate silicate.

Dumortierite is thought to promote mental discipline, especially in regard to learning new things, and as a memory aid.  Some believe that dumortierite aids meditation and psychic vision.

Fluorite

Fluorite is a crystal that comes in colorless, blue, yellow, purple, red, orange, green and nearly black.  The color is often zonal or spotty, which can be improved through irradiation treatments.  Some fluorite is banded, showing multiple colors in the same stone.  Fluorite is relatively soft - only a 4 on the Mohs hardness scale.

Fluorite is the state stone of Illinois as it is mined in the southern part of the state.  It is also mined in other U. S. locations, Canada, South Africa, Thailand, Peru, Mexico, China, Poland, Hungary, Norway, England and Germany. 

Fluorite is thought to increase concentration and aid in decision making.  Some believe that fluorite can help heal the respiratory system and relieve arthritis.

Garnet

Garnet includes a wide range of gemstones that have similar chemical compositions.  Most people think of the red varieties of garnet, however garnet comes in nearly every color.  Each type of garnet has its own range of colors:  almandine (red to violet-red), spessartite (yellow, rose, orange, and reddish-brown), pyrope (deep red with brownish tints), grossular (colorless, yellow, yellow-green, green, brownish-red, orange and black), and andradite (colorless, yellow-green, dark green, brown and black). 

The most valuable garnets are demantoid (a green garnet in the andradite group), Tsavorite (an emerald green garnet in the grossular group), Spessartite (also called spessartine, mandarin orange color), and rhodolite (a rose-red to violet-red garnet in the almandine family).  Recently a blue color-change garnet has been found in Tanzania, which is also quite expensive.  There is also a red garnet that is mined by ants in Arizona called Ant Hill garnet.  Ant Hill garnets are "mined" when the ants remove them from the ground as they build their ant hills and are then collected by the owners of the land on which these ant hills are found.  Garnets range from 6.5 to 7.5 on the Mohs scale of hardness.

Garnet is thought to help have a successful business.  When worn as jewelry, garnet is thought to aid with self-esteem.  Some believe that red garnets can help cleanse and purify the thyroid and spleen when held over the body.

Goldstone

Goldstone is manmade, and therefore technically not a gemstone.  Goldstone is made up of copper and silica glass that forms tiny crystals when melted together.  Goldstone comes in both a coppery-gold and dark blue color.

Hawk's Eye

A finely fibrous quartz aggregate with cocidolite hornblende inclusions that can be blue-gray to blue-green.  It is often found with tiger's eye, which is a pseudomorphed form of hawk's eye.  When cut into cabochons, hawk's eye displalys a phenonmenon called chatoyancy (cat's eye effect).  Hawk's eye is a 7 on  the Mohs scale of hardness.

Hematite

Hematite is colored by iron oxide and can be black, gray or red-brown.  It is known in Germany as bloodstone because when it is cut, the saw coolant becomes colored red from the iron oxide in the stone.  As a result, for many years, hematite was worn as an amulet against bleeding.  When polished, hematite has a metallic sheen.  Hematite is a 5.5 to 6.5 on the Mohs hardness scale.  Hematite is found in Brazil, China, Canada, England and Germany.  Do not confuse hematite with hematine, a manmade version of hematite.

Hematite is thought to improve relationships and increase intuition.  Some believe that hematite can aid in iron absorption.

Herkimer Diamond

Herkimer Diamond is a double pointed rock crystal quartz that has been faceted by nature.  When they were first discovered in Herkimer, New York, they were thought to be diamonds, hence the name.  Like all quartz, Herkimer diamonds are a 6.5 to 7.5 on the Mohs scale of hardness.

This form of rock crystal quartz is thought to have very strong power due to its double terminated crystal.  Herkimer diamonds are used to assist with out of body travel.  Some also believe that the Herkimer diamond can aid in balancing the body and emotions.

Howlite

Howlite is named after the geologist who first identified it, Henry How.  It is a member of the borate mineral family and is generally found in evaporate deposits.  In its natural state, howlite is white to gray, often with gray, brown or black veining.  This stone is very porous and so it is often dyed to resemble turquoise, coral, lapis lazuli and other stones.  Unscrupulous vendors often try to sell dyed howlite as these other stones.  Undyed howlite is sometimes sold as "white turquoise," "white buffalo turquoise," and "buffalo stone." 

Howlite is softer and lighter weight than actual turquoise, with only a 3.5 rating on the Mohs hardness scale.  The lighter weight and the (much) lower cost of howlite compared to turquoise actually can make it useful for earrings as you can use larger stones without having overly heavy earrings at a reasonable cost.

Howlite is believed to relieve stress and to eliminate insomnia due to an over active mind.  Some also believe that howlite can strengthen teeth and bones.

Iolite

Iolite is found in various shades of blue to blue-violet and exhibits strong pleochrosim (showing different colors depending on the angle at which the stone is viewed).  The best iolites are similar in color to tanzanite.  Iolite is sometimes called water sapphire because of its blue color and its use in ancient times as a navigation tool by sailors.  Iolite has a rating of 7 to 7.5 on the Mohs hardness scale.

The ancients beleived that iolite assisted with creativity in artists.  In modern times, iolite is believed to aid shamanic  journeys.  Some belive that iolite can help heal th eyes and that it helps stimulate memory.

Jade

There are two types of stone that are categorized as jade; for centuries they were thought to be the same stone.  In 1863, it was discovered that "jade" is actually two different minerals and one was named jadeite and the other nephrite.  It takes an expert to determine the difference between the two minerals.

Jadeite comes in green, white, yellow, reddish, brown, violet and black.  The most valuable color is the emeral green transluscent jadeite colored by chromium.  This color is often referred to as Imperial Jade.  Jadeite is rated 6.5 to 7 on the Mohs hardness scale.

Nephrite comes in the same colors as jadeite, but is often striped or spotted.  Nephrite is actually more common than jadeite and has a 6.5 rating on the Mohs scale.

Many imitations of jade are sold on the market and jade is also made into doublets (where a thin layer of jadeite is glued to a quartz backing) to increase the transluscency and to imitate Imperial Jade.  Jadeite and nephrite are both sometimes dyed to improve or give color.

Because of its long history, there are a number of legends and beliefs about jade that have developed over the years. 

Jade is considered a money stone and is believfed to help you use your money creatively and productively.  Jade is said to help you make important business decisions.  Jade is also thought to guard against misfortune. 

Some also believe that jad helps the body heal and is especially helpful for the kidney, heart and stomach. 

Jasper

Jasper is a microcrystalline quartz that some gemologist and geologists classify as a chalcedony; others place jasper in a separate category within the quartz family.  Jasper comes in every color, although single color jaspers are rare - most jaspers are striped, spotted, or have orbicular patterns.  As with all the quartz family, jasper is 6.5 to 7.5 on the Mohs hardness scale. 

There are numerous varieties of jasper; the names of these varieties tend to reflect the color, pattern, or the place wher the jasper is found.

It is thought that all forms of jasper can help balance the emotional energy in the body and therefore, one should always have a jasper.

Desert Jasper

Desert jasper is also known as polychrome jasper and peninsula jasper.  It was recently found in the deserts of Madagascar.  It actually comes from three separate but nearby sources, hence the varying names.  It was discovered by geologists searching for more ocean jasper and was named for the multiple colors the stones display.

Desert jasper is said to help with stability and balance.

Leopard Jasper

Leopard jasper exhibits spots, but it comes in a variety of colors no leopard ever wore! 

Leopard jasper is said to assist with connection to your spirit animal and with shamanic travel.  Some also believe that leopard jasper can assist in self-healing.

Moukaite Jasper (a.k.a. Mookaite Jasper)

Moukaite jasper is a very colorful form from Australia that displays yellows, pinks, purples, reds, orange-reds, and browns.  In Australian tradition, moukaite provides strength.

It is thought that moukaite encourages the owner to seek new experiences, and encourages calmness.  Meditating with moukaite is said to increase your ability to see multiple solutions to a problem.  Some also beleive that moukaite can help with the treatment of glandular problems and stomach disorders.

Ocean Jasper

Ocean jasper is also known as orbicular jasper and was found off a remote coast in Madagascar.  Ocean jasper could only be mined at low tide, however the source seems to be depleted.  Colors in ocean jasper include white, green, pink, lavender, red, black, blue, brown and gray.  The spots, wavy lines, and multi-colored floret patterns in ocean jasper are the fossils of ancient marine animals.

Ocean jasper is believed to contain positive vibrations that lift spirits and bring joy.

Red Jasper

Red jasper is colored by iron and can range from a rusty red to a deep wine color.  Red jasper is one of the few varieties of jasper that can be found in relatively uniformm color.

Red jasper is believed to provide protection at night and is considered lucky for actors.

Wild Horse Jasper

Wild horse jasper is mottled and comes in quite a few colors. It seems to come primarily from the Wild Horse Canyon mine in Oregon - Idaho.  I have also seen it listed as Wild Horse Picture Jasper or Picture jasper.  It has quite a bit of plant material in it and comes in greens, browns, tans, etc. 

It is often confused with crazy horse stone which has similar mottling, but is a limestone.  It is also sometimes confused with Wild Horse Stone, which is a magnesite (white stone) with hematite veining (usually purple hued brown or rosy brown) that is found in the Gila Wilderness Area of Arizona. 

Kunzite

Kunzite is a spodumene crystal that comes in pale pink to pink-violet to pale violet colors.  Unfortunately, the color often fades when exposed to light, so wear this gem for evening occasions.  Kunzite was discovered in 1902 and was named after the well known gemologist, G.F. Kunz.  Kunzite is a 6 to 7 on the Mohs hardness scale.

Those who wear kunzite are believed to have good fortune and it is sometimes considered a symbol for pregnancy.  Kunzite is also considered a calming relaxation stone.  Some believe that if you gaze at a kunzite, your daily stress will be reduced.

Kyanite

Kyanite is a blue to colorless or blue-green mineral.  Most kyanite found is not of a quality that can be faceted, however the mineral is attractive when the blades are polished.  The necklace in the banner of this website is polished blades of kyanite and one of my favorite necklaces.  Facet grade kyanite is a deep velvety blue that rivals the color of Ceylon sapphire.  Because of the differences between the mineral and crystal forms, kyanite has a wide range of hardness.  Facet grade kyanite is the most durable at 7 on the Mohs hardness scale.  Mineral grade kyanite hardness varies across and down the crystal cleavage; from 3.5 to 6 on the Mohs hardness scale.

Ancients believed that kyanite suspended from a human hair could follow the earth's magnetic force and travelers sometimes used it as a compass.  Modern beliefs about kyanite include that kyanite can restore energy balance and that it can create stillness and tranquility.

Lapis Lazuli

Lalpis lazuli (pronounced as one word, and more commonly called lapis) is a rock that contains small amounts of numerous minerals, including augite, calcite, diopside, mica, hauynite, hornblende, and pyrite; however the primjary mineral is lazulite.  The best lapis stones are an even azure blue with well distributed fine pyrite inclusions or veining.  Paler blue lapis is sometimes referred to as denim lapis as the color resembles well worn washed blue denim.  Lapis lazuli is a 5 to 6 on the Mohs hardness scale.  The finest lapis comes from Afghanistan.

Be careful when purchasing lapis lazuli as there are imimtations on the market; howlite for example, is often dyed to resemble lapis. 

It is believed that using lapiz lazuli while meditatitng can help clarify matters in your mind and that wearing a lapis ring can help you become a channel.  Some believe that for healing, lapis should only be used by a healer as the stone is very powerful.

Larimar

Larimar is a rare form of pectolite that comes in white, light blue, green-blue and deep blue.  Although pectolite is found in many places, this form contains copper rather than the more common calcium as a colorant, resulting in this lovely blue stone called larimar.  Larimar is rated 4 to 4.5 on the Mohs scale of hardness.  This color of pectolite is only found in the Dominican Republic.

Some believe that Edgar Cayce  predicted the discovery of larimar when he stated that a blue stone would be discovered in the Caribbean where Atlantis could be found.  It was found by a monk and a local who named the stone after his daughter Larissa and the Spanish word for the sea.

Larimar is believed to soothe emotions and to increase feminine power.  Others believe that larimar can help new mothers who suffer from depression and stress.

Labradorite

Labradorite is a feldspar that exhibits a lustrous play of color on the surface of the stone called labradorescence.  Labradorite is generally gray to gray-black with mostly green and blue metallic luster.  The most valuable labradorite displays a full spectrum of colors in the luster.    Labradorite that displays this full spectrum of color exceptionally well is often marketed as Spectrolite.  There are some labradorites that are suitable for faceting.  These crystals come in yellow, brown and clear.  Recently a deep cherry red labradorite was marketed, however this find has since been determined to be andesine or labradorite that has been dyed.  Labradorite is rated 6 to 6.5 on the Mohs hardness scale.

Labradorite is believed to aid in strengthening intuition and stimulating the imagination.

Leopardite

Leopardite was originally found near Charlotte, North Caroline and is described by geologists as a combination of feldspar and quartz, spotted by oxides of iron and manganese.  The result is an interesting rock with spots that give the stone its name.  Several other locations in North Carolina are now mined for leopardite and it is the state's gemstone.  Other similar type stones have been found in other countries, and all of them that have spots seem to be called leopardite.

Leopardite is believed to promote acceptance and understanding of oneself and others.  Use this stone when you are struggling with judgment of self or others.  Some believe that leopardite has a peaceful energy that will assist with letting go of conflict, insecurity and loss of control.

Malachite

Malachite is formed from copper-containing solutions in or near copper ore deposits.  The resulting colors are pale green to emerald green and green-black.  The deposit layers show as concentric rings or lines when the stone is cut.  Malachite is a rather soft stone with only a 3.5 to 4 rating on the Mohs hardness scale.

Malachite sometimes forms with azurite, and is then called Azur-malachite.  Malachite can also form with turquoise and chrysocolla, which is then called eilat stone. 

Malachite is said to protect the wearer from accidents and has been used to aid business success.  Some also believe that malachite can be used to eliminate nightmares if you keep one in the bedroom.

Moldavite

Moldavite belongs to the tektite group of minerals.  The tektites in moldavite were formed when a meteorite hit the earth and melted the rock.  Moldavite crystals are generally small and are bottle green to brownish-green.  Moldavite is a 5.5 on the Mohs hardness scale. 

Moldavite is thought to work as a spiritual catalyst and to make dreams more vivid and meaningful.

Moonstone

Moonstone is a feldspar with a unique sheen that gives the stone its name.  Moonstone can be orthoclase, plagioclase, albite and microcline feldspar.  Moonstone can be yellow, blue, multicolored and colorless.  The sheen on the moonstone comes from a lamallar structure, which causes adularescence and can also cause a cat's eye effect, known as moonstone cat's eye.  Moonstone is a 6 to 6.5 on the Mohs hardness scale.

Moonstone is thought to bring good fortune, enhance intuition, and to bring success in love.  Some believe that moonstone can help balance the homone cycles.

Muscovite

Muscovite is the most common of the mica group of minerals, and is also known as potash mica.  It comes in a variety of colors, including green (fuchsite), colorless, gray, brown, yellow, and (rarely) red or violet.  Muscovite can be transparent to transluscent.  The name comes from Muscovy Glass, which references its use for windows in Russia many years ago.  Muscovite is a soft rock - only a 2 to 2.5 on the Mohs scale of hardness.

Muscovite is thought to aid with inspiration, problem solving and intuition. 

Fuchsite

Fuchsite is the green variety of muscovite and iti has a vitreous to pearly luster.  It is a very soft stone, with only a 2 to 2.5 rating on the Mohs hardness scale. 

Fuchsite, like all muscovite, is said to aid with inspriation, problem solving and intuition.  Fuchsite is also believed to decrease insomnia and relieve emotional shock.

Lepidolite

Lepidolite is the pink, lavender-gray to purplish form of mica or muscovite.  The color comes from manganese.  Lepidolite was discovered in the eighteenth century and was originally known as lilalite (from the Hindu word for play or game).  As with all micas, lepidolite is soft - only 2.5 to 3.5 on the Mohs hardness scale.

Lepidolite is known by healers as the peace stone.  Lepidolite is thought to encourage independence for setting and attaining goals and to protect from outside influences,  Some also believe that lepidolite attracts good luck to those who carry it and that it will drive away negative energy.

Obsidian

Obsidian is a volcanic rock that comes in black, gray, brown and green.  Obsidian does not have minearl crystals, therefore is is not a true rock - it is actually volcanic glass.  Although more commonly a solid color, obsidian can have a gold or silver sheen when polished, and some obsidian rocks have "flowering" gray -white inclusions that are orbital in nature.  This included type of obsidian is sold in the trade as snowflake obsidian.  Other color variations include brown mottled with black (mahogany obsidian), and purple, green and gold bands of sheen in black (rainbow obsidian).  Obsidian is a 5 on the Mohs scale of hardness.  

Obsidian was revered by ancient cultures and it was used for making tools, masks, weapons, mirrors, and jewelry.  Some believe that obsidian can protect against depression and can block negativity.

Gold Sheen Obsidian

Obsidian that is formed when volcanic lava comes into contact with water, cooling the lava quickly sometimes produces a glassy texture containing small bubbles of air that are aligned along layers during the cooling process.  These bubbles can produce a sheen effect in the obsidian.  Sometimes this sheen is golden. 

Gold sheen obsidian is believed to enhance the ability to achieve worldly success through the expression of your talents. 

Mahogany Obsidian

Brown obsidian combined with black obsidian often has a reddish tone in the brown and is referred to as mahogany obsidian.  The Hawaiians believed this variety of obsidian was sacred.

Mahogany obsidian is said to have a gentle energy that will protect its owner.  Some believe that mahogany obsidian can relieve pain and improve circulation.

Rainbow Obsidian

Obsidian that is formed when volcanic lava comes into contact with water, cooling the lava quickly sometimes produces a glassy texture containing small bubbles of air that are aligned along layers during the cooling process.  The bubbles can produce a sheen effect in the obsidian.  Sometimes this sheen is multi-colored and therefore referred to as rainbow obsidian.

Some believe that rainbow obsidian can help expand consciouness and sharpen the senses.

Snowflake Obsidian

Sometimes when the lava cools, it includes some other minerals that tend to "flower" in the obsidian.  These inclusions tend to be gray to white and when small, look like snowflakes, hence the name.

Snowflake obsidian is said to balance the mind, body and spirit.

Onyx

Onyx is a microcrystalline quartz in the chalcedony family.  Onyx is the name given to banded microcrystalline quartz where the base is black and the upper layer is white.  Sardonyx has a brown base, carnelian has a red, base, etc.

Onyx is also the name used to describe uni-colored chalcedony, such as black onyx, unless the chalcedony is blue or green.  (Blue chalcedony is called just that, and green chalcedony is called chrysoprase.)  Like others in the microcrystalline quartz family, onyx has a rating of 6.5 to 7.5 on the Mohs scale.

Onyx is believed to help release negative emotions such as sorrow and grief.  Onyx is also worn to guard against negativity.

Opal

Opal is an amorphous quartz.  Opals are divided in to three groups: opalescent precious opal, red to yellow fire opal, and common opal.  The opalescence of this group of quartz is caused by tiny spheres of the mineral cristobalite that are trapped in a siliceous jelly within the host rock.  Opal always contains water, however the percent of water can very and the water can evaporate out of the opal over time, reducing the color and value.  For this reason, rough opal is stored in water, and cut opals should be stored in damp cotton.  Some lapidaries state that polishing the back of the opal cabochon, or faceting the opal so that all sides are polished, will seal the water inside the stone.  Opals are a 5.5 to 6.5 on the Mohs hardness scale.

Common Opal

Common opal is opaque with no play of color in the stone.  Common opal is marketed under names such as blue opal, pink opal, Peruvian opal, Oregon opal, etc.  The names generally indicate either the color of the common opal or  the place where the common opal is found.

Blue common opal is believed to soothe erratic emotions and enhance courage.

Fire Opal

Fire opal can be colorless to yellow to orange to cherry red.  The best quality fire opals are clear to transparent, however most fire opals have a milky appearance.  There is even a unique fire opal that is nearly colorless, but has a bluish sheen and red play of color.  This unique fire opal is called a sunflower or girasol opal.  Fire opals are found in Mexico and Brazil and are usually identified by their place of origin and color, for example a Mexican yellow fire opal. 

Fire opal is said to stimulate ideas and to draw in money and customers to your business.  Some believe that fire opal gives energy to the wearer.

Precious Opal

Precious opal comes in two forms: white or milky opals and color host opals.  The best known form of precious opal has a host rock that is clear to milky in color.  Colored host precious opals have a host rock that is dark gray, dark blue, dark green or gray-black.  Although black host rock is known, it is extremely rare.  A recent find of precious opal in Ethiopia has some orange to dark orange host rock.  The flashes of color that precious opals are known for can vary from tiny pin prick to large flashes of color.  Each type of color flash has its own name. 

Because of the rarity of precious opal and the associated high cost, precious opal doublets and triplets are common on the market.  In a doublet, precious opal is layered on top of a harder rock slab, often an agate or onyx.  In a triplet, precious opal is layered between a slab of harder rock on the bottom and a layer of rock crystal quartz on the top.  In addition to reducing the cost of the opal, the layers actually help to protect the softer precious opal from damage when worn.

Precious opal is found within a matrix rock and is sometimes cut to showcase the opal and matrix together.  This was referred to as opaline or opal matrix for many years.  Currently is is called boulder opal in the trade.

There are now many man-made versions of opal on the market.  Some are quite beautiful, and while expensive for a man-made stone, they are much more affordable than real precious opals.  However, beware - if it looks amazing and is inexpensive, it's man-made opal.  Real high quality precious opals displaying lots of color can cost thousands of dollars.

In Europe, precious opal is thought to be unlucky unless it is your birthstone.  However, in Asia, precious opal has represented loyalty and hope.  Many believe that precious opal is a protection stone.

Opalite

Opalite is a man-made opalized glass resin that is fused with metal to create an opalescent effect.

Pearl

Pearls are organic gemstones that are produced by salt water molllusks, freshwater mussels, and rarely, by snails.  Pearls are formed when a foreign body makes its way into the shell of the animal and the animal attempts to protect itself by secreting mother-of-pearl (calcium carbonate, a.k.a. aragonite) called nacre, around the foreign body.   The luster of the pearl is created by the overlapping  of the aragonite platelets, which not only form the sheen, but also the color of the pearl based on how light refracts off the nacre.  The color of the pearl is also determined by the type of mollusk or mussel and the location of the mollusk or mussel, as water in different locations contains different minerals that affect the color.  There are two types of pearls:  natural and cultured.  Natural pearls are referred to as pearls; cultured pearls must always be designated as such. 

Pearls are soft, only a 3.5 to 4.5 on the Mohs hardness scale, however their spherical shape and compact layers make them difficult to crush.  Pearls that are well cared for can last 100 to 150 years, and there are pearls that are several hundred years old that appear to be in very good shape.

Pearls are highly sensitive to extremes of heat and dry air, as well as high humidity.  Chemicals, perspiration, make-up, etc. can have a detrimental effect on your pearls, so they should be wiped clean with a soft damp cloth after each wearing. 

Most pearls on the market - certainly pearls that most of us can afford - are cultured pearls.  Humans introduce a foreign object into the mollusk or mussel so that the animal will produce a cultured pearl.  This is usually done by placing a bead the size and shape desired into the salt water mullusk.  With fresh water mussels, a piece of mantle from another mussel is inserted to create the cultured pearl.

Pearls and cultured pearls come in many shapes, sizes and qualities.  Like other gemstones, they are graded from AAA to D.   Many cultured pearls are dyed to obtain colors normally found in natural pearls, and some are dyed to suit current fashion.  Both natural and cultured pearls are sometimes bleached to obtain a whiter color.

Pearls are thought to promote prosperity and success. Some believe that pearls can promote calm.  Some also believe that pearls can help with digestion and can reduce emotional stress.

Peridot

Peridot is also known by its scientific name, olivine.  Peridot is found in very pale yellow-green to dark grass green and often brown colors.  Very dark stones are sometimes lightened by burning and rare cat's eye and star peridot have been found.  I even own one with a "horse tail' inclusion commonly found in the Russian demantoid garnet - it's an amazing peridot from Pakistan cut by Bill Vance.  Peridot is a 6.5 to 7 on the Mohs hardness scale

Peridot has been known and valued as a gemstone for thousands of years in the Middle East.  Crusaders brought back peridot to Europe during the Middle Ages, where is was used for ecclesiastical purposes.  Peridot was especially popular during the Baroque Age.  Ancient people believed that peridot was a gift from Mother Nature and that dreaming about peridot could foretell of impending danger.  Cleopatra's emeralds were actually peridot!

In modern times, peridot is considered a spiritual stone.  Wearing a peridot on a necklace is believed to soothe the throat.  Some also believe that peridot can help heal the gall bladder and liver.

Pietersite

Piertersite is a relatively new find in gemstones.  It was discovered in 1962 by Sid Peiters as he was prospecting in Namibia.  This original find was named after Peiters once he registered the find with the British Mineralogical Society the next year.  The African source of Peitersite is mainly crocidolite which morphs into quartz.  The stone is brecciated with bands, swirls and blotches of blue, gold and/ or red tiger eye giving the stone chatoyancy.  It is rated a 5 on the Mohs hardness scale. 

In 1993, a second source of Peitersite was found in Hunan Province in China.  This is a more fibrous stone that is magnesium rich alkalic amphibole.  This source produced gold, red, blue and sometimes deep golden brown brecciated stones.  This source is now believed to be depleted. 

The Namibian source is also nearly depleted (reportedly) and so this stone is becomming difficult to obtain.  Blue is the rarest color.

Peitersite is said to help us accept chaos and find order, especially in our creative lives.  It is also believed to help you relax and to support your will power.  Some also believe that peitersite will help balance hormones that regulate growth, sex, metabolism, blood pressure and body temperature.

Prehnite

Prehnite is a calcium aluminum silicate mineral that is not often found in crystal form.  Crystals can be pale yellow-green to brown-yellow and prehnite cat's eye crystals have been found.  Prehnite is rated a 6 to 6.5 on the Mohs scale of hardness.

Prehnite is thought to enhance your intuition and ability to recognize truth when worn.  Some believe that prehnite can help heal kidneys, bladder, chest and lung problems.

Pyrite

Pyrite is composed of either iron sulfide or iron disulfide.  It is a brassy yellow to gray-yellow color, and has often been compared to the color of gold.  Its common name is "fool's gold."  Pyrite is found all over the world, and comes in several types of crystals that when polished have a metallic sheen.  Pyrite is a 6 to 6.5 on the Mohs scale.

The Incas used pyrite as mirrors, and in many cultures pyrite has been seen as a symbol for money and luck due to its resemblance to gold.  Many believe that pyrite can be used to block negative energy and can help you overcome feelings of inertia and inadequacy.

Prasiolite

Prasiolite is the leek-green macrocrystalline quartz that is rarely found naturally.  This leek-green color occurs when light colored amethyst or yellow quartz that contains iron is heat treated. (Normally when you heat amethyst it turns a darker color purple, or it turns yellow.)  Prasiolite is often mislabeled as green amethyst in the trade.  Prasiolite is a 7 on the Mohs scale of hardness.

Quantum Quattro Silica

A relatively new stone found in Namibia in 1996, quantum quattro silica is made up of royal blue shattuckite, robins egg blue chrysocolla, dark green dioptase, smoky quartz and light green malachite. I'm searching for more information on this stone - if you know more about it, please let me know!

Quantum quattro silica is said to bolster the immune system.  Others believe that this stone can help heal grief from past traumas.

Quartz

Minerals of a similar nature are grouped as quartz. The group is divided into three large groups.  The first is microcrystalline quartz or chalcedony, which includes agates, fossilized woods, chrysoprase, heliotrope/bloodstone, carnelian and onyx for example.  The second group is the macrocrystalline quartz which includes amethyst, citrine, smoky quartz, rock crystal quartz, and rose quartz to name a few.  Jasper is included in the chalcedony group by some geologists; others categorize jasper as a third group of quartz.  The third group, amorphous quartz includes the opals, such as precious opal, fire opal and common opal.  Quartz is found in every color and the names given can vary depending on the tone and saturation of the color, the source of the quartz, etc.  Quartz stones range from 6.5 to 7.5 on the Mohs hardness scale.

Some of the most interesting quartz stones have inclusions that give the quartz stone both its name and character.  For example, quartz can have golden rutile needle-like crystals or schorl (black tourmaline) needle-like crystals included in the stone that create interesting patterns in the clear to milky quartz crystals.

Druzy Quartz - Druzy, (aka drusy, druse) refers to the tiny crystals that sometimes form on or inside another rock.  In natural druzy quartz, the druzy gets its color from the host rock, unlike many other quartz crystals.  However, natural amethyst, citrine, etc, druzy crystals are often found.  Druzy can also be found in other types of rocks such as garnet, cobalt, crysocolla, etc. 

Druzy quartz is a 7 on the Mohs hardness scale like other quartz rocks, however the tiny crystals can be damaged if care is not taken when worn. 

Druzy quartz is thought to aid in balancing and increasing your energy.  Some also believe that is aids in extrasensory perception.

Lemon Quartz

Lemon quartz is a macrocrystalline quartz that is pale to lemon yellow.  Although closely related to citrine, lemon quartz is more yellow and has less of an orange to red undertone than citrine.  With some stones, it would be difficult to classify them as either lemon quartz or citrine as the colors are so close.  Lemon quartz, (like most quartz colors) is often treated to improve the color.  With the lemon quartz color, the process is usually to irradiate the stones after cutting.  As with all quartz, the Mohs hardness rating for lemon quartz is 6.5 to 7.5,

Some believe that lemon quartz can help you obtain prosperity and creativity.

Lodalite

Lodalite is a macrocrystalline quartz with inclusions that seem to resemble a coral reef, a garden, or a landscape.   The inclusion colors can be pink, green, brown, yellow and red - stones often have more than one color in the inclusions.  These unique crystals are said to be found in only one location, the Minas Gerais area of Brazil.  The highest quality lodalite is the clear crystal quartz with inclusions, however other colors of macrocrystalline quartz may contain these inclusions as well. 

BTW, inclusions is a broad term used by rock hounds, gemologists and geologists to describe "things" that are "included" accidentally in the crystals of some rocks as they solidify.  These inclusions can be other cyrstals, air bubbles, plants, bugs, etc.   Some of them actually add value to the stones, as is the case with lodalite.

Lodalite is considered a very powerful journeying stone and is sometimes used by shamans to induce visionary experiences and healings. 

Purple Quartz

I have recently seen purple quartz on the market - and no, it isn't the same as amethyst.  Purple quartz is a macrocrystalline quartz, and it is a very pale blue-lavendar color with a unique sheen, much like you would see on a moonstone (feldspar).  I am searching for more information on this lovely pale lavender stone.

Rose Quartz

Macrocrystalline quartz that is pale to dark pink is called rose quartz.  Transparent crystals are relatively rare, with most being transluscent to opaque.  Some rose quartz has rutile needle inclusions that create a star rose quartz when cut into a cabochon. Much of the rose quartz that is mined is crackled and unsuitable for faceting or use in jewelry.  Rose quartz is a 7 on the Mohs scale. 

Rose quartz is thought to be a symbol of love and will improve your marriage when placed under your pillow.  It is also thought to improve the sense of self-worth when worn.  Some believe that rose quartz provides inner peace and can work to rejuvenate the skin.

Rutliated Quartz

Crystal rock quartz gemstones that contain mineral rutile inclusions are called rutilated quartz.  Rutile crystallizes before the quartz host crystal forms, resulting in the rutile cyrstals being trapped within the quartz crystal.  The rutile forms small needle-like crystals that may be golden or red.  Black needle-like crystals are also sometimes formed in quartz and called rutile, however they are in fact, schorl or black tourmaline and are more properly termed tourmalinated quartz.  As with most quartz stones, rutilated quartz is a 6.5 to 7.5 on the Mohs hardness scale.

Rutilated quartz is believed to bring hope and function as an antidepressant.  When the rutile crystals are red, the stones are said to intensify the energy of the stone.  Rutilated quartz is also believed to aid with respiratory problems and is said to help balance a sad or weak heart.

Smoky Quartz

Macrocrystalline quartz that is brown to nearly black is called smoky quartz.  Transparent crystals are plentiful, and some have a lovely golden tone, which in the trade are sometimes referred to as whiskey or cognac quartz.  Very dark stones are heat treated to lighten the color.  Heating sometimes changes the stone to yellow citrine color.  Smoky quartz can have rutile inclusions that create interetsing patterns in the crystals.  Smoky quartz is found worldwide.

For many years, smoky quartz was labeled as smoky topaz.  Topaz is a completely different mineral and this topaz label is incorrect.  Citrines are also sometimes marketed as topaz.  Buyer beware!

Many believe that smoky quartz is an endurance stone that can help promote personal pride and a joy in life.  It is said that smoky quartz facilitates your ability to get things done.  Some also believe that smoky quartz can help relieve depression.

Red Creek Stone

Found in 2010 in northwestern China, this stone is still being tested to determine its nature and mineral properties that cause these lovely colors..  The miners were looking for turquoise when they found this lovely red, green, yellow, blue-gray and black stone instead.  LIke turquoise, it must be stabalized to be cut and polished.  In the trade, Red Creek stone is being sold as jasper, however, Red Creek stone in much softer than cryptocrystalline quartz (jasper).  It is named for the stream that runs through the mining site.  No ultrasound or steam cleaning on these stones as they will shatter.

Rhodochrosite

Rhodochrosite is found in pale pink to raspberry pink, sometimes having cream or white stipes.  Much of the rhodochrosite mined has layer of pink tones as well as cream or white layers.  The stones can be transluscent to opaque.  The most valuable are the raspberry pink transluscent crystals, however many people prefer the shades of pink and cream in the opaque stones.  Rhodochrosite may have some matrix rock included in the stone that can be brown or black.  Rhodochrosite is a 4 on the Mohs scale.

Rhodochrosite is also known as Inca Rose, probably due to the location of early finds.  Rhodochrosite has formed in stalagmitmes of abandoned Incan silver mines. 

Rhodochrosite is thought to soothe the heart and stimulate feelings of love and compassion.  Some believe that rhodochrosite can help heal reproductive organs and reduce blood pressure.

Rhodonite

Rhodonite is rose pink to red, usually with black dendritic inclusions.  Transluscent crystals are rare, and rhodonite is generally cut into cabochons.  The black inclusions are manganese dioxide.  Rhodonite is a 5.5 to 6.5 on the Mohs hardness scale.

Rhodonite is thought to soothe the nervous system; simply holding this stone is said to promote relaxation and well being.  Some believe that rhodonite can help ward off negativity.

Rhyolite

Rhyolite is an igneous volcanic rock composed primarily of quartz and alkali feldspar.  It may also contain hornblende.  Chemically it is said to be the same as granite, however rhyolite is extrusive, where granite is plutonic. 

It was mined by ancient Native Americans in eastern Pennsylvania but is found in many areas of the US.  There is a ghost town in Nevada that was named for the rhyolite mine that was once worked near there.  Rhyolite got its name in 1860 from a German geologist who had seen it while travelling in the U.S. Rocky Mountains.  The color can be white, gray, greenish, reddish, goldish, or brownish.  It can be even in color or banded, and in some cases, it is even blotchy looking.  Although the grain is usually very fine - you can't really see the crystals - in some rhyolite, there are large crystals that can be seen, hence the blotchy look.  This is more correctly called porpyhritic or uneven crystal sizes in the rock.

Rhyolite is between 5 and 6 on theMohs scale of hardness.  No ultrasound or steam cleaning on rhyolite stones.

Sonoran Dendritic Rhyolite

A new find of rhyolite comes from one remote mine in Mexico.  This is a gorgeous but rather rare type of rhyolite and can be difficult to purchase.  This particular rhyolite has wonderful dentritic patterns that are dark red-brown to black.  They appear to form when the rhyolite fractures during the crystal growth process.  The fractures then fill with iron-rich silica, solidifying  the rhyolite stones one again.  The silica creates the reddish brown quartz dendrites in this rhyolite. 

Because Sonoran dentritic rhyolite is relatively soft, it usually takes a matte polish.  The colors of this particular rhyolite are pastel gray, gray-green, soft reds, yellows and creamy whites.  The patterns created by the colors and the quartz dendrites are stunning!

Rhyolite is believed to aid in working towards goals in a diligent and proficient way.  It is also thought to help the wearer deal with change.  Some believe that rhyolite can work to heal skin problems.  Others believe that rhyolite will strengthen the bond between children and animals. 

Sagenite (Sagenitic Quartz)

Sagenite is a rare form of microcrystalline quartz.  It was discovered may years ago in the western U.S.  Purple sagenitic quartz is a monochomatic agate that has been penetrated by radiating sprays of foreign matter that form a net-like pattern (sagena is Latin for net).  The color purple may be due to ferric iron or ferric oxide bonded to an additional hydroxide ion - or light interference which scatters the wavelenth in the violet range.  What ever causes this purple color is just lucky for us!

Sapphire

Sapphire is the common name for a group of gemstones called corundum.  The only color of corundum that is not labeled sapphire, is red, which is designated as ruby.  The various colors, other than blue, are designated by their color: yellow sapphire, green sapphire, etc. Sapphire without a further designation is always blue.  Good quality sapphires are also often designated by their mine location, for example Ceylon Sapphire or Kanchaniburi Sapphire.  Although they lack the disperson of a diamond, colorless sapphires are often used as accent stones in jewelry to reduce the cost.

Sapphire can have rutile inclusions, which in sufficient quantity cause a 6-ray star or asterism.  Corundum, or sapphire, is very hard with a rating of 9 on the Mohs hardness scale. 

Sapphires can be grown in a laboratory in any color, but the most commonly grown colors are red, blue and an orange-pink called Padparadscha Sapphire.  Some lab grown corundum is made to resemble other gemstones that cannot be grown in a laboratory, such as tourmaline.  All laboratory grown sapphire and ruby must be labeled as such.  Chemically and optically the corundum grown in a lab will be identical to the stones mined from nature.

Sapphire is thought to increase clarity of thought and increase perception.  Some believe that sapphire can aid in healing a sore throat.

Ruby

Ruby is the red corundum and is considered the most valuable of all the corundum family.  Some feel that ruby is the most precious of all gemstones - more precious than a diamond.  The optimal color of a ruby is termed "pigeon blood red" and is rare.  Many rubies on the market are rather opaque, and crackled rather than transparent, clear crystals.  Ruby is colored by chromium, which acts as a growth inhibitor in the crystals, so large rubies are especially valuable. 

There are clarity enhanced rubies on the market today. This means that the cracks in the ruby crystal  have been filled with glass to improve the clarity of the stone, and the stone must then be labeled as fissure filled.  This process does improve clarity, but lowers the value of the stone substantially.  Laboratory grown rubies  are also commonly found and must be labeled as such.  Their color can be quite red to very dark reddish-pink. 

Rubies can have rutile inclusions that in sufficient quantities can cause a star or asterism effect when cut correctly. 

Rubies are considered a powerful gemstone that can be worn for protection.  When given as a gift, rubies are traditionally a symbol of love and/or friendship.  Some believe that rubies can improve passion in your life.  Ruby is also believed to improve circulation of the blood stream.

Sardonyx

Sardonyx is banded chalcedony in the microcrystalline quartz family.  In the layered chalcedony stones, a stone with black on the bottom layer and white on the top layer is called onyx.  When the bottom layer is brown the stone is term sard-onyx or sardonyx (because sard means brown).  If the bottom layer is red, the stone should be labeled carnelian-onyx, however in the trade, both brown and red base layer chalcedony is generally called sardonyx.  Sardonyx is a 6.5 to 7.5 on the Mohs scale.

Sardonyx is thought to enhance your willpower, stamina and vigor.  Some believe that sardonyx can bring happiness and stability to your marriage.  Others place sardonyx at each corner of their home to prevent theft and crime from entering the home.

Seraphinite

Seraphinite is found only in the Lake Baikal region of Siberia, Russia.  It is characterized by swirling silvery white patterns in a dark to sea-green background. 

The name seraphinite is said to be a derivitive of seraphim, and is therefore thought to be useful in connecting with the angelic realm. Others believe that seraphinite encourages living from the heart, and aids in the restoration of health and balance.

Serpentine

Serpentine is a mineral with varying chemical properties and varying appearances.  It comes in all hues of green with various inclusions.  Strictly speaking, serpentine comes in two types:  antigorite, which is "leafy" serpentine, and chrysotile, which is fibrous serpentine.  Asbestos is actually a fibrous variety of serpentine.  Serpentine is a 2 to 5.5 on the Mohs scale.

In jewelry, we use two varieties of serpentine.  The first is called bowenite, an apple green serpentine with small spots or stripes.  The second is called williamsite, which is transparent green with black inclusions.  Serpentine combined with marble is marketed in the trade as serpentine, and much of what is seen today is this combination of serpentine and marble.

When serpentine containing chromium decomposes, the mineral becomes rose-pink to purple and is called stichtite. 

It is believed that serpentine can help you find inner peace and balance mood swings.  Some also believe that serpentine can relax cramps and help with kidney and stomach illnesses.

Sodalite

Sodalite is named for the sodium content in the mineral.  Sodalite comes in nearly all shades of blue, which is often interspersed with white clacite.  Sodalite is a 5.5 to 6 on the Mohs scale of hardness.  Stones that are predominantly blue will be more valuable than those that are predominantly white.

Sodalite is thought to bring inner peace and to harmonize the conscious and unconscious mind.  Some believe that wearing sodalite can help you lose weight. 

Sunstone

Sunstone is actually feldspar that has numerous red hematite and/or iron inclusions that give it the red-orange or brown sparkle sunstone is known for.  Oregon sunstone has copper inclusions and is the only known source of this type of sunstone.  Gemologists would call this stone aventurine feldspar rather than sunstone and it would be classified as a species of plagioclase called oligoclase.  Sunstone is a 6 to 6.5 on the Mohs scale.

Sunstone is considered a protective stone and is worn to give you extra energy when you are ill or under stress.  Some believe that sunstone promotes harmony among your organ functions.

Tanzanite

Tanzanite is a member of the zoisite mineral family.  It was given its name by Tiffany and Company when they introduced the blue form of zoisite to the market in 1967.  Gemologists accepted this name, but prefer to use the more correct term of zoisite.  Although tanzanite comes in all shades of blue and violet, the best quality stones are ultramarine blue to sapphire blue.  Because tanzanite is pleochroic, good quality stones actually display three colors: blue (predominant), violet, and red.  In addition, good quality tanzanite that appears very blue in natural light, may appear amethyst purple under artificial light - so always look at the stone in natural light before purchasing.  Rough tanzanite tends to be brown to yellow, although the blue color is found.  Heating the brown to yellow tanzanite generally improves the color to some shade of blue or purple.  Tanzanite is 6.5 to 7 on the Mohs scale of hardness.

Tanzanite is said to link the heart to the mind, and to promote compassion.

Tiger's Eye

Tiger's eye is a yellow-gold to gold-brown form of quartz that has the fibrous crocidolite hornblende inclusions common in hawk's eye  quartz or tiger iron.  In tiger's eye, a pseudomorphism occurs in the hawk's eye where the fibrous structure is maintained.  This results in the chatoyancy effect that gives this stone its name - tiger's eye.  Tiger's eye is a 7 on the Mohs scale of hardness.  Most of the tiger's eye on the market is from South Africa and Australia, although it is also found in Burma (Myanmar), India, and California in the U.S.

Heating the gold-brown form of tiger's eye will change the gold and brown to red and black, leaving the chatoyancy.  Tiger's eye is also  dyed many colors for the fashion jewelry trade.

Tiger's eye is said to bring good luck and protection to the wearer.  Some believe that tiger's eye can help focus the mind.

Topaz

Topaz comes in yellow, red-brown, light blue, pink, pale green and colorless.  Natural pink is the most valuable color, however historically most topaz placed into jewelry was a golden color with pink undertones (Crayola named a crayon this color).  This golden-pink color is now rare and is often referred to as Imperial Topaz.  Other natural colors are referred to as Precious Topaz.  Natural colorless topaz that has not been treated is sometimes referred to as silver topaz or white topaz.  Topaz is an 8 on the Mohs scale of hardness.

In the trade today, most topaz sold is colorless topaz that has been treated in some way to give it color.  London Blue topaz and other blue forms are treated with radiation to obtain the blue color.  This process is safe, and the color is permanent.  Other topaz are treated with vapor deposition to give a multi-colored appearance.  This treatment is also safe, but can be damaged as it rests on the surface of the stones.  Care must be taken when wearing and, especially, when cleaning these vapor deposition treated stones.

Topaz is considered a soothing stone that will heal and energize.  Silver or white topaz is thought to purify emotions and actions.  Imperial topaz is believed to improve your confidence and give strength.

Tourmaline

Tourmaline is found in every color of the rainbow.  Crystals of one color are actually rare - most exhibit multiple shades of one color, or multiple colors within one crystal.  Each color of tourmaline has its own name; scientific groupings are also given based on the composition of the tourmaline.  Some tourmalines are heat treated to lighten the color. All toumalines have a 7 to 7.5 rating on the Mohs hardness scale. 

There is currently no process for producing tourmaline in a laboratory, however some lab grown corundum (sapphire) and spinel are colored to look like tourmaline so they can be sold as tourmaline. Tourmaline can be identified by its double refraction and strong pleochroism.

Achroite (Colorless or White Tourmaline)

Colorless tourmaline crystals are very rare, and therefore rarely seen in jewelry.  I've never seen one in person.

Dravite (Yellow to Brown Tourmaline)

Yellow, brown, cognac, gold-brown, etc. tourmalines are all classified as dravite.  While many of these stones are very beautiful in their color, they are less valuable as fewer collectors want them. 

Indicolite (Blue Tourmaline)

Blue tourmaline is categorized as indicolite (a.k.a. indigolite) and is one of the more rare colors found in tourmaline.  Many indicolite tourmalines are actually blue-green in color, with the value of the stone increasing with the true blue of the stone.

Indicolite is thought to promote calming and to bring happiness to the wearer.  Others believe that indicolite can help develop psychic abilities.

Rubelite (Pink to Red Tourmaline)

Pink to red tourmaline is called rubelite.  In this category, true pink is often referred to as pink tourmaline rather than rubelite.  The term rubelite is often reserved for the ruby red or the red-violet colors of tourmaline.  The closer the color of a rubelite is to ruby red, the more valuable the stone will be.  True pink tourmaline is also highly sought after in the current market, and is therefore more expensive as well.

Pink tourmaline is said to be a gentle stone that nutures and relaxes.  Some believe that pink tourmaline has the ability to help the wearer be more open to love.

Siberite (Lilac to Violet Tourmaline)

Lovely lilac to violet shades of tourmaline are classified as siberite, however some gemologists include these colors with the rubelites.  These purple shades are among the rarest colors of tourmaline.

Schorl (Black Tourmaline)

Black tourmaline, or schorl, is the most common color of tourmaline and lacks the transparency or transluscency of the other colors.  Schorl was not used for jewelry until recently - now chips and beads are readily available.  Small needle-like crystals of shorl are often found in quartz crystals.  These are referred to as tourmalinated quartz.

Schorl is believed to bring luck and happiness.

Verdilite (Green Tourmaline)

Green tourmaline is categorized as verdelite.  Within this category, there are two classifications:  green tourmaline and chrome tourmaline.  Green tourmaline is the most common color and chrome tourmaline (which resembles true emerald green) is the most valuable of all tourmalines.

Verdilite is said to bring success to the wearer and a joy for life.  Some also believe that verdilite strengthens the heart.

Watermelon (Red, green and white or colorless Tourmaline)

Because tourmaline crystals frequently have a different color "skin," when sliced tourmalines often show multiple colors.  When the colors are green, red (or dark pink) and white (or colorless), the tourmaline is often called watermelon.  Watermelon tourmaline can have green on the outside with red/pink on the inside, or it can have red/pink on the outside and green on the inside.  

Other crystals with multiple colors are simply called bi-color, tri-color, etc.

Watermelon tourmaline is said to attract love and remove guilt caused by conflicts.  Some also believe that watermelon tourmaline can calm the mind.

Tourmalinated Quartz

Tourmalinated quartz is clear or cloudy macrocrystalline quartz that contains schorl (black tourmaline) needle inclusions.  When the rock was formed, the schorl crystals formed before the quartz sollidified, trapping the needle-like schorl crystals within the quartz.  As with all quartz, tourmalinated quartz is a 6.5 to 7.5 on the Mohs scale of hardness.

Tourmalinated quartz is thought to give luck, but should only be used when powerful luck is required and put away at other times.

Turquoise

Turquouise is found on many continents and is sky blue, blue-green, or apple green in natural form.  The name means "Turkish stone" likely because the stone was originally brought to Europe through Turkey.  The most famous turquoise (and most valuable) comes from the Sleeping Beauty mine in the southwest U.S., however, good quality turquoise comes from many other mines.  Solid turquoise with no matrix is fairly rare.  Matrix can be brown (limonite), dark gray (sandstone), or black (jasper). 

Turquoise should always be removed from jewelry before soldering as the heat will change the color ( and not in a good way!).  Over time, perspiration, oils, soaps, and chemicals, etc. will also change the color of natural turquoise.  Because of this, turquoise rings should always be removed  before washing your hands or working with any chemicals.

Turquoise is relatively soft, 5 to 6 on the Mohs scale, and very porous.  This can cause the turquoise to lose water content over time which will also change the color of the stone.  As a result, turquoise is generally immersed in oil or paraffin to seal the stone.  Or, the stone is coated in a resin or polish to seal the stone.  This process is called stabalization and does not damage or reduce the value of the stone.  Low quality turquoise is also frequently dyed to obtain a better color of blue or to change the color of the stone altogether.  Dyed turquoise is not as valuable as natural turquoise.

The best color of turquoise generally comes from the top layers of the mine deposits; as the mining moves deeper, the turquoise tends to be lighter or white.  This is sometimes referred to as chalk turquoise.  Unfortunately, the name chalk turquoise is also sometimes used to refer to howlite that has been dyed a turquoise color and to magnesite that has been similarly dyed.  Reconstituted turquoise is also often marketed as turquoise or chalk turquoise, but is in fact bits and powdered turquoise left on the cutting room floor that is mixed with paste and shaped into "stones."  Recently wild horse stone (a soft white magnesite that has natural veining of hematite that makes it look  like turquoise) is being marketed as buffalo turquoise or as white turquoise.

There are also many imitation turquoise stones on the market.  When purchasing turquoise, it is best to know your source well - and buyer beware!

Turquoise is thought to be a symbol of friendship and to protect the wearer from negative energy if given by a good friend.  Some believe that turquoise can help with stomach problems and inflammatory illnesses.

Wavellite

Wavellite has traditionally only been sold and used as a specimen - it is only 3.5 to 4 on the Mohs hardness scale and must be stabalized with resin to use in jewelry.  Wavellite is usually found in thin seams or wrapped around matrix so it can be difficult to find pieces large enough to cut into cabochons.  Consequently, matrix is often included in the cut stones.  The best wavellite comes from Arkansas.  Wavellite suitable for cutting is usually shades of green with radial patterning.  The matrix can be sandstone, limestone chert, or flint.

Do not use steam or ultrasound cleaning on these stones.

Zircon

Zircon's chemical name is zirconiuim silicate and it should NOT be confused w ith the diamond simulant sold as cubic zirconia, which is a lab grown zirconium oxide.  Real zircon is often confused with diamonds, and this is the reason a manmade simulant of the stone was developed to be used as a cheap substitute for the real thing.

Zircon comes in brown, red, yellow, green, blue, black and colorless.   They are a 7.5 on the Mohs scale so this stone is very durable as well as beautiful.  Most zircons are heat treated to improve or change the color.  The blue stones are the most valuable and they are almost all heat treated to obtain the blue color, although natural blue zircons can be found. 

Zircon is the oldest known mineral on earth!  It is said to aid spiritual growth and promote wisdom.