Florida State Symbols: State Gem Moonstone

Here's an interesting fact:  Florida's state gem isn't found in Florida!  Florida chose moonstone as the state gemstone to honor the moon landings and all other astronaut controlled space flights that were launched from Kennedy Space Center in Florida.

Moonstone is an orthoclase feldspar (feldspar being a group of minerals).  The visual effect is caused by light diffraction withing the layers of the micro-structure of the stone:  alternating layers of orthoclase and albite feldspar form at high temperatures, then cool.  When these layers cool, they cause the adularescent sheen that we all love in moonstone.  This type of feldspar is also refered to as adularia.

This first photo is a high resolution scope shot of the layers of the feldspar from crystalinformation.com

Moonstone comes in white, blue, peach and orange, gray, green and rainbow.  The best moonstones come from Sri Lanka (facet grade transparent with blue flash), Burma, and India, however moonstone is found in many places including the U.S. - just not in Florida!  This photo is of a rough moonstone from Burma showing how it looks once cut into a nice cabocon. How did the ancients ever figure out what this stone would look like cut?  Photo from gia.edu

Since the rough doesn't really show the moonstone's adularescence, it takes a skilled cutter to bring out the desired effect in the stone.  The height of the stone is critical, plus you have to align the axes of the crystal correctly in order to show the light effect.  Faceting requires even more skill to show the desired sheen.  The blue flash moonstone is becoming difficult to find and the price for this stone has risen sharply in the last few years.  This photo is from gia.edu and likely shows Sri Lankan high quality faceted moonstone.

Moonstone has been used to make jewelry for centuries; it was especially popular in Art Nouveau jewelry (1890-1910).  However, moonstone is a 6 - 6.5 on the Mohs scale of hardness and requires some care when wearing.  This gemstone got its name from either the ancient Greeks or Romans (depending on who you read) as they thought the light diffraction in the stones resembled the light of the moon. This next picture is of a lovely peach moonstone cab from gemselect.com

For those who are interested in the uses of and powers of moonstone here are a few attributes of the various moonstones.

Blue and cat's eye moonstones are said to promote clarity and inner vision.  They are helpful in seeing life lessons and help balance yin and yang energies.

White moonstone is said to stiumlate psychic perception.

Peach moonstone is believed to support the heart and stimulate the mind.  It is also helpful to those with weight problems.  Carry or wear one to love and value yourself and assist in separating food from emotional needs.

Rainbow moonstone is believed to defelct negativity and ease emotional trauma.

This last picture shows a rough moonstone crystal that actually shows the blue flash - it's set in a ring made by Beijo Flor and is for sale on Etsy.

 

 

 


 

Florida State Symbols: State Stone Agatized Coral

Florida has a state stone and a state gem, although technically speaking, their state stone is a fossil.  I'll begin with the state stone, agatized coral (a.k.a. silicated coral and fossil coral). 

Coral is the external skeleton of ocean polyps; it's mostly lime.  When the polyps die, over time silica from water replaces the lime, creating what is called a pseudomorph (one mineral has been replaced by another mineral without losing the original form and shape). This process takes 20+ million years to occur.  Most of the Florida agatized corals are from the Oligocene-Miocene period.

Trace minerals give these fossil corals a variety of colors:  white, gray, brown, black, yellow, peach, orange, tan, amber and red.

This first picture is of a coral nodule that has been sliced in two and is from Fossil-Treasures-of-Florida.com.

While most living corals are now protected, fossil corals are not.  Most of the agatized corals were originally rugose and tabular coral species.  The oldest fossil corals are over 450 years old!  This photo is of a pile of fossil corals from the Withlacooche River and was taken by River Rat and posted on the Fossil Forum.

Because it's now quartz (silica), agatized coral is a 7 on the Mohs scale so it is quite hard and has long wear as a cut stone.  The first humans to inhabit Florida used the agatized coral to make tools such as spear points and knives.  Archeologists have found tools dated as old as 5000 years old near St. Petersburg.

This pile of fossil corals cut into cabochons is from ereferencedesk.com and shows the range of colors available.

Agatized corals are found in three primary locations in Florida:  Tampa Bay  near Ballas Point; the Econfine River; and the Withlacoochee/Suwannee River beds. This last picture is a close up of an agatized coral cab from Florida that I found on Pinterest with no indication of who actually took the picture (my apologies to the photographer).

Delaware State Symbols: State Mineral Sillimanite

Delaware's state mineral is sillimanite.  Sillimanite is one of three alumino-silicate polymorphs; the other two are kyanite and andalusite.  Sillimanite is named after Benjamin Silliman (an American chemist  and the first professor to teach minerology at Yale University) by George Thomas Bowen who first described this rock.  It was first found in Connecticut in 1824.  In Delaware, sillimanite is found in the Brandywine Springs area in Newcastle County and near the Hoopes Reservoir.  The material found in Deleware is massive and fibrous.  It was named the state mineral because of the huge boulders of it found in the region.  This picture is a piece of sillimanite from Delaware. Photo from mindat.org

Usually colorless, gray or white, but can, on rare occasions, be brown, pale yellow, yellow-green, blue-green, or blue.  Generally transparent to transluscent, sillimanite can be splintery, acicular (like needles) or fibrous (as is the case in Delaware).  Sillimanite is common in metamorphosed sedimentary rock and can be found in biotite schist with quartz segragations.  This pic is of a piece of sillimanite schist thin section under a microscope from geosec.biz.  Gotta get me one of those scopes!

While it is 6.5 to 7.5 on the Mohs scale, sillimanite has perfect cleavage making it very difficult to cut and facet. Native American Indians used the fibrous schist for making tools. Facet grade sillimanite has been found in Burma (Myanmar) and in Sri Lanka.  This photo is of a facet grade rough crystal from rruff.com

It makes a pretty faceted stone though, so a good cutter can come up with some nice stones for setting.  This photo is from skywalker.cochise.edu

  Finally, due to the fibrous growth, sillimanite can be cut into cabochons that show a nice cat's eye effect.  I've even seen a few that had star effects.  This photo is of a cat's eye sillimanite from gemselect.com

 

Delaware State Symbols: State Fossil Belemnite

Delaware doesn't have as many state symbols as some states, but they do have a state fossil and a state  mineral.  I'll start with their state fossil the belemnite.

More specifically, their state fossil is the Bellemnitella americanus belonging to the phyllum mollusca and class cephalophoda.  This marine mollusk was related to modern day cuttlefish, although they looked more like modern squids.  The belemnite lived for a period of about 140 million years, disappearing about 65 million years ago at the end of the Cretacious Period.  The name comes from the Greek, belemnon, meaning like a dart or javelin.  This is a depiction of the anatomy of a belamnite from www.ucmp.berkely.com

These little cephalopods were only about 2-6 inches long, but they were fast, efficient carnivores that caught small fish and marine animals with their 10 hooked tentacles.  They also had a beak-like jaw.  The tail had a bullet shaped feature of the skeleton called the rostrum or guard. The part that is found as a fossil is the rostrum or guard from the back end of the animal.  This fossil is the hard external skeleton; modern squids do not have this, so they are more closely like modern cuttlefish. 

These creatures lived all over the world.  This is a picture of a fossil rostrum that was found in the U.K. Photo from demon.co.uk/fossils

The best place to look for belemnites in Delaware is in the dredge spoil piles near the mouth of the Chesapeake and Delaware canals, just west of St. Georges.  You can also find them just east of the north side of the Reedy Point Bridge.  The best time to look is right after they dredge the canal.

According to www.fossilguy.com, in this same location (where you can find belemnites), you can also find pelecypods; generally two kinds - exogyra costata (pic from thefossilshop.com)

 

and pyncnodonte mutablilis (pic from newton.physics.uiowa.edu).

These will generally be small, no more than 3 inches. Finally, you can also find fossil sharks' teeth at these sites.

This last belemnite pic is of an opalized belemnite fossil - would LOVE to find one of these!  The pic is from ferrebeekeeper.wordpress.com

If you would like more information on where to locate fossils in Delaware, check out www.dgs.udel.edu/delaware-geology/fossil-sites-delaware

 

Connecticut State Symbols: State Mineral Almandine Garnet

Although Connecticut doesn't have a state gemstone, it does have a state mineral that is also a gemstone - the group of garnets classified as almandine (iron aluminum garnet).  These garnets are found in numerous locations throughout Connecticut: the most famous spots for finding garnets include Colchester, Redding and Roxbury.  Most garnets found in Connecticut are deep burgundy red, often with some brown undertones.  Gem quality garnets in the state are fairly rare, although some nice ones have been found.  This photo of Connecticut garnet crystals comes from ereferencedesk.com

The garnets that are not this nice are used for abrasives and emery boards.  And, while most are burgundy red, you can actually find garnets in many other colors in Connecticut.  Other garnets found here include pyrope (magnesium aluminum garnet), grossular (calcium aluminum garnet), spessartite (manganese aluminum garnet) and andradite (calcium iron garnet).  Garnets can be found in igneous rock pegmatites, coarse granite and in granite gneiss. This photo of garnet in matrix is from the Yale Peabody Museum of Natural History in New Haven.

The best known place to collect garnets in Connecticut was Green's Garnet Farm near Roxbury Falls.  Unfortunately, it is currently closed for any collection.  There is an Essonite garnet outcrop near West Redding; you'll need permission from the owner to collect there.  From the West Redding Train Station, follow the tracks about 1/2 mile and look for a rock outcrop on the left.  You'll need heavy tools to collect at this site.

Herb Heweitt's Gem  Mine near Haddam in Middlesex County re-opened in 2013.  It's a group of pegmatite quarries.  Collection for a fee.

This is a photo of the Connecticut Gem and Mineral Society collecting at Roxbury before the site closed.

There are also plenty of other minerals to collect in Connecticut.  Here are a few you can find:  quartz, albite, amphiboles, muscovite, fluorapatite, zircon, schorl, pyrite, olivine, tourmaline, beryl, lepidolite, topaz, opal, fluorite, calcite, dolomite, diopside, epidote, zoisie, danburite, forsterite, feldspars, prehnite and amazonite.

Connecticut State Symbols: State Fossil Dinosaur Track

I've been to Connecticut many times, but for some reason I never realized that dinosaurs are a very big deal there.  In the mid 1960s, while breaking ground for a new state building, over 2000 dinosaur tracks were uncovered in the Connecticut sandstone formation in the Connecticut Valley.  The tracks are believed to have been left by large bipedal carnivores during the Early Jurrasic period (200 million years ago) along what was then a shallow lake.  This area is now one of the "foremost dinosaur track locations in the world" according to the Connecticut state website.  This photo is from the statesymbolsusa.org site and is a close up of a dino track at this location near Oak Hill.

Note that this is a three-toed track ending with a claw.  This is called a Eubrontes Giganteus and refers to the shape and size of the track, NOT the species of dinosaur that made the track.  There were multiple dinosaurs with three toes on their feet, and it is difficult when no other fossils are present to determine which dino made a specific track.  Scientists who have studied the CT tracks believe the dinosaurs were possilbe relatives of Dilophosaurus or from a platerosaurid.  Probably an 18-20 foot long predator.  A typical Eubrontes track is 25 - 50 centimeters long.  Here is a picture of the quantity of tracks at the Oak Hill site where there is now a state park.

The Dinosaur State Park opened in 1968 and is celebrating its 50th anniversary in 2016.  There will be special events all year, with a kick off on April 16.  About 500-600 tracks have been preserved under a geodesic dome; the rest were re-buried for preservation.  One of the fun things to do at the park is to make a plaster casting of a real dinosaur track.  For more information on the park go to dinosaurstatepark.org

But the Dino park isn't all there is to do in Connecticut if you love dinosaurs.  The state has put together a Dino Trail which includes participating hotels with discounted rates. In addition to the State Park, the Connecticut Science Center in Hartford has a pterosaur fossil and a fossil dig pit for kids. Here's a photo from their web.

The Yale Peabody Museum in New Haven has lots of dinosaur skeletons on display.  Here's a photo from their web.

The Dinosaur Place at Nature's Art Village in Montville has a fossil dig, a gemstone dig and a place to pan for gold.  All are, of course, salted so kids can find a souvenir, but it's  fun way to introduce kids to rockhounding and to learn about fossils. They have "life size" dinosaurs throughout.

Finally, on the Dino Trail you can go to Lake Compounce in Bristol.  This is an amusement park, however they have a dinosaur "expedition" with animatronic dinosaurs.

Unfortunately, past glacial activity has wiped away most fossils in what is now Connecticut.  However, the Connecticut Valley used to be a tropical/equatorial forest with lots of fish, amphhibians, insects, reptiles and dinosaurs, who all left evidence behind.  Footprints and small plant and fish fossils are the most abundant.  Fish fossils are generally found in the black shale sediments of the Valley. So, while not easy to find, there are fossils out there, and hey - getting to see all those footprints is pretty cool.

 

 

Colorado State Symbols - State Fossil Stegasaurus

I don't remember why, but as a child, the stegasaurus was always my favorite dinosaur.  In the pictures the face always seems so cute.  But, these huge herbivores were up to 30 feet long!  Still, that was small compared to many of the dinosaurs around at the time.

The first stegasaurus fossils were found in Colorado in 1876 by Othniel Charles Marsh in Morrison, Colorado.  But, Marsh didn't find a complete skeleton, so he thought he had found an aquatic turtle-like creature.  It wasn't until more specimens were found that we were able to figure out what the fossils were - and that there were several species of stegasaurians. 

Marsh called his first find a stegasaurus (roofed lizard), because he believed the plates on the back lay down along the back like roof shinges, or like armour.  Eventually, a fossil was discovered with the plates still attached, showing that the plates actually stood up on end. This photo of mother and child fossils is from the statesymbols.usa.org web site.

The stegasaurus lived in the Mid-Jurassic to Late Cretaceous period or about 150 million years ago. They were herbivores and appear to have lived in herds.  Each species had a specific number and arrangement of plates on their back, and all had spikes on their tales.  The tail had no ossified tendons, so it is likely that the tail was highly flexible and it is believed that the stegasaurus was able to use those spikes with great accuracy for defense.  Species had between 17 and 22 plates and spikes.  The species first found in Colorado, and the state symbol is Stegasaurus Armathus, also known as Stegasaurus stenops.  S. stenops was probably the largest dinosaur in this family.  Fossils from about 80 individual S stenops were found in the Morrison formation. 

It's obvious from the fossils that stenops had a short neck and a small head so it probably ate low bushes and shrubs.  When I was a kid, stenops was always depicted dragging his tail, however scientists now believe that the tail was likely held high in the air.  You can see from this photo of an actual fossil  find that it would take some time to figure out exactly what this dinosaur might have looked like - this specimen is in the National Museum of Natural History and the photo is labeled stegasaurus roadkill.

There have been four theories over the years regarding those plates on the back.

1) Marsh initially believed the plates laid flat along the back like shingles on a roof for armour.  That's why he named it the "roofed lizard" or stegasaurus.  This theory was later disproved.

2) Marsh later believed that there might have been a single row of plates standing down the back.  This theory was also disproved by later fossil finds.

3) A later theory was that there was a double row of plates along the back, in parallel.

4) The most current theory is that there were two rows of alternating plates.  By the late 1960s this had become the dominant theory based on fossils that were found with the plates still attached.

We still aren't sure what purpose the plates served, but they could be as large as two feet tall.  The plates were not attached to the skeleton.  They were bony cored scales, growing in tihe skin, similar to what you see on a crocodile or some lizards today.  The stenops plates had lots of blood vessels through them leading scientists to speculate that the plates may have served several purposes.  These plates may have helped regulate body temperature similar to the way elephants' ears help cool their bodies.  The plates may also have been used as a display, turning colors (or blushing) to attract a mate or as a warning to predators.

Although the stegasaurus was large, the other dinosaurs living at that time, such as allosaurus and ceratosaurus probably ate them.

The tiny head, in comparison to the large body, has let to the theory that S. stenops had a very small brain about the size of a walnut.  Recent research has uncovered a space along the spinal column that may have held a second brain that allowed the stenops to react quickly with those deadly tail spikes when attacked. 

There are only 6 skeletons of stegasaurus on display in the U.S. A.  One is in the Museum of Natural History in Denver - it was discovered by a teacher and students from Canyon City High School! This is a photo of that fossil on display as if under attack by another dinosaur.

 

 

                                   

 

Rockhounding in Colorado

In poking around for information on rockhounding in Colorado, I found too much information to share! For example, just in the Salida, CO (again in Chaffee County) area I found:

Brown's Canyon; follow Chaffee County Roads 193 and 194. Old mines can be found off the side roads. You can locate fluorite, placer gold and copper. Dig through the tailings.

Marshall Pass: along the old abandoned railroad grade you can find jasper, marble, geodes, picture sandstone, rhyolite, and fossils.

Poncha Pass: between San de Cristo Range on the southeast, and Sawatch Range on the west and northwest, you can find sheelite. You need a black light at night to locate this mineral.

Ruby Mountain: (misnamed when garnets were found) near Nathrop, six miles south of Buena Vista you can find spessartite garnet, yellow topaz, and obsidian in perlite. Make sure you stay on public land.

Nearby on Dorthy Hill and Sugarloaf Mountain you can find smoky quartz and sanadine.

At the abandoned Sedalia Copper Min, 4 miles south of Salida in Trout Creek Hills, you can find almandine garnet, staurlite, actinolite, epidote, corundum (sapphire), spinel, horneblend, chrysocolla, malachite and willemite.

This picture from irocks.com  is of an amazonite and smoky quartz combo.

In the Taylor Mountain, Cree Creek area you can find quartz crystals, limonite cubes, malachite and galena in the tailings of old mines.

In the Trout Creek Pass area you can find jasper, agate, and pink microcline feldspar. The south and east slopes are best.

This is a photo from the summit of Trout Creek Pass from youtube.

So, as you can see, just in one county, you could spend many happy weeks looking for - and finding - all kinds of rocks!

 

Colorado State Symbols - State Gemstone Aquamarine

If you watch Prospectors on the Weather Channel, you know that Colorado's state gemstone is aquamarine.  The largest aquamarine crystal ever found in North America was found on Mt. Antero by Steve Brancato.  It's now is the Denver Museum of Nature & Science. This photo of the crystal is from the Denver Post by C. Walker.


Mount Antero and neighboring White Mountain are both in Chaffee County Colorado. They are the center of aquamarine mining in the state. Antero is the 10th highest peak in Colorado, and rockhounding on either mountain is for experienced people in good physical condition - these are steep mountain peaks. Plus, much of the area has claims, so you have to be careful where you search for aqua crystals.

Mt. Antero's granite stock, is actually part of the much larger batholith of quartz monzonite - probably late Mesozoic or Tertiary age. The granite stock has many beryllium-rich pegmatites and veins. Minerals typically found in these pegmatites and veins include: beryl (the blue is aquamarine), quartz (lots of smoky quartz here), phenakite, bertrandite, fluorite, muscovite, molybdonite, topaz, amazonite and various combinations of these minerals.

Here are a couple of pictures of crystals found on Mt. Atero. The first one is from padisgems.com , the second is from irocks.com.

Colorado is surpassed only by California in the number of minerals found there; Chaffee county alone has over 127 minerals and 774 minerals can be found in the state. Thirty varieties of gemstones can be found in Colorado.

This is a picture of Mount Antero (from wikipedia) - as you can see, many of us couldn't get up the mountain, let alone get heavy rocks back down. It's only open about 4 months out of the year, and that high up, the weather is often ugly even during the summer months. If you watch Prospectors, you get a close up view of the rocky terrain and how quickly the weather can change.

There are public access places available to look for aquamarine - but make very sure  you are on one of them!

 

 

Colorado State Symbols - State Mineral Rhodochrosite

This week I'm starting on Colorado's state rocks and fossils, beginning with the Colorado state mineral, rhodochrosite. Designated in 2002, rhodochrosite is found in many areas of the state, but none of the mines are as famous or as important as the Sweet Home Mine near Alma, Colorado. This picture is of "The Searchlight" rhodochrosite crystal found in the Sweet Home Mine.

Sweet Home mine is about 90 miles southwest of Denver located at the timberline on the Mt. Bross side of Buckskin Gulch. The crystals found here are considered the best in the world - transparent to translucent pink-red rhombohedron crystals. Less pure and more pinky crystals are also found here and in other mines around the state. Even less pure crystals are pink, white and brown banded opaque. All are beautiful manganese carbonate minerals. The crystals are fairly soft - only about 3 to 4 on the Mohs scale AND the crystals have perfect cleavage in three directions, so they are quite difficult to cut. This picture is of pink rhodochrosite crystals from one of the mines near Silverton.

Rhodochrosite is often found in silver mines in Colorado and in Argentina where it got the alternate name.  Turns out magnesium carbondate destroys the amalgmation process used in mining silver - so they used to throw the rocks away!  Sweet Home mine was originally a silver mine - until the 1960s.  Currently, the Sweet Home mine is not producing any rhodochrosite.  It takes eight people to maintain the Seet Home mine.  It takes a great deal of time to find pockets of rhodochrosiste - it can be as long as two years between significant finds. 

In 1994, workers in the Sweet Home mine discovered a tunnel, about 2.5 meters in diameter with thousands of pieces of rhodochrosite.  It took six weeks to collect them all.  It was then purchased by the Coors Co. and donated to the Denver Museum of Natur & Science in the Coors Mineral Hall.  The "Denver Wall of Rhodochrosite" was reconstructed and has over 3000 specimens.  Some of the crystals are over 7 cm long.  This is a picture of workers reconstructing the Wall.

And this one of mining in Sweet Home.

Lots of other former silver mines have rhodochrosite in them - they're all privately owned as well. Some of the other mines are: Climax Molybdenum mine near Leadville; John Reed mine, also near Leadville; Julia Fisk Mine near Leadville; the Gilman mine in Gilman, a ghost town; Mary Murphy mine near St. Elmo, a ghost town; American Tunnel mine near Silverton; Grizzly Bear mine near Ouray; and the Mountain Monarch mine also near Ouray. This pic is of the Mary Murphy mine from the Colorado ghost towns web.

Rhodochrosite is also found in Argentina (their national mineral) and Romania (first discovered there). The Incas believed that the rhodochrosite crystals were the blood of former rulers turned to stone. It's found in many silver mines and in caves in what is now Argentina and is also known there as Inca Rose or Rosa del Inca.

Some believe that rhodochrosite helps to conduct energy and can boost self-confidence. Some also believe that these pink crystals balance and enhance love on all levels This picture of a specimen or rhodochrosite shows where the nickname comes from. It's from gemstonemeanings.us. The cab is a nice one from astrolika.com The faceted rhodochrosite is from Mt. Lily gems.

 

 

 

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