California Rockhounding

So, that wraps up California. I'll start on Colorado next week.

BTW there are so many other things to look for in California. You can find tourmaline at the Himalaya Mine in Santa Ysabel and at the Pala Chief Mine, Ocean View Mine or Stewart Mine just outside San Diego. Nephrite jade can be found in many areas of the state. If you go to California, check out some of these museums that have great displays of interest to rockhounds of all ages. There are many more!

Natural History Museum of Los Angeles County http://www.nhm.org/site/

Page Museum at the LaBrea Tar Pits http://www.tarpits.org/

University of California Museum of Paleontology at Berkley http://www.ucmp.berkeley.edu/

California State Mining and Mineral Museum at Mariposa
http://www.parks.ca.gov/?page_id=588

This picture is of a family searching for tourmalines at High Desert Gems and Minerals in California.

California State Symbols - State Mineral Gold

The California state mineral - no surprise here - is gold. The California Gold Rush (1848-1855) brought over 300,000 people to the California territory to settle the state. Many were Americans, but people came from all over the world - Latin America, Australia, Asia, and Europe. Most didn't find their fortune, BUT, they did build roads and towns, established ranches and farms,and drew the railroad west to the coast. The very violent era of the Gold Rush was followed by a period of anti-foreign legislation and vigilante attacks against (especially) Latin American and Chinese immigrants. The Rush also resulted in a state-sponsored genocide of the Native Americans who had lived in California's Great Basin for over 14.000 years.

At one time, there were over 16,500 gold mines in California - most are now gone; the busy towns, now ghost towns and even most of those have disappeared. The state has saved some of them in Historic Parks, among them Marshall Gold Discovery State Historic Park, Columbia State Historic Park, and the California State Historic Park (Shasta). This picture is of Bodie; this ghost town has a hollow grave stone used to hide booze during prohibition, and is said to have a curse.

Gold mining in California during the Gold Rush started with simply picking up nuggets and flakes since the gold was so plentiful and easy to find. They then moved on to panning gold (sluicing water and silt in a pan so the heavier gold settles in the bottom). This method is still frequently used today. But, as gold became harder to find, more invasive methods of mining were developed. Placer mining (think panning on a much larger scale with machines) became common, then by 1853, hydraulic mining and dredging came into practice. Hydraulic mining had the unfortunate effect of causing run off of gravel, silt and heavy metals; this led to pollution of rivers, streams and groundwater. Hard rock mining was also used; this involved extracting gold from (usually) quartz rock using mercury as an amalgam. This caused additional pollution. Really, any commercial mining of gold today is a heavy pollutant to the area around the mines. Fortunately, most gold on the market today is actually recycled gold. There are still active commercial mines in California and it remains an important economic source for the state. So, in 1965 when gold was declared the state mineral, Governor Ed Brown recognized the "intimate" history gold and California have.

There is a current little Gold Rush going on in California. The historic drought has caused rivers and streams to drop to the point were gold is now accessible where it once was not. This picture is of gold in quartz from the state's geological site.

Gold can still be found all over California. Maps for the various regions can be requested from several state agencies. In dry southern California, hobbyists often use metal detectors to locate gold; further north, panning is still common. Information from the California Bureau of Land Management provides information on where looking for gold is legal for the general public.

Most sites are under claim, so you must have permission from the owner (and usually pay a fee) to look for gold; however, there are places where there is no claim and you can look for gold (often for free). Some of the free places I've found include: Butte Recreation, Keyesvill, Redding, South Yuba River, Merced River, Auburn State Recreation Area; El Dorado National Forest, Tahoe National Forest; Hangtown's Gold Bug Park, Marshall Gold Discovery State Historic Park, and Columbia State Historic Park.

Make sure you get exact locations in these areas. This is how I found my own California gold flake - at a park where you can pan. Now, it would have been nice to go out looking in a more natural setting, but I was short on time and money and, I have to say, I had a blast learning how to pan and finding my own little piece of gold. I highly recommend it - and the kids that were there seemed to really enjoy it too. Great family vacation! These pictures are from the State website and Parent magazine respectively.

  

 

California State Symbols - State Gemstone Benitoite

I got a little behind on my states - California's saber tooth cat was so interesting it was hard to follow!

But, the California state gem is benitoite (ben-ee-toe-ite) and it's a very rare and beautiful gemstone - one of my favorites. This color suite of benitoite is available for sale from the owner of the mine, Dave Schreiner. It shows the range of color for the gemstone.

I covered benitoite when I did the rarest gems on earth - and benitoite is indeed one of the rarest. The crystal structure is also one of the rarest - hexagonal, class ditrigonal-dipyramidal. Benitoite disperses light better than a diamond (so, very sparkly) but this facet grade is found in only one place - the head of the San Benito River in San Benito county California. The crystals tend to be small, and we still don't know what colors them blue, but one carat stones cost around $3500-$6000; larger stones run about $10,000 per carat. This photo of benitoite crystals in matrix is from the mine site.

Benitoite was discovered by J.M. Couch in 1907 while he was prospecting; in 1907 George Louderback identified the stones as a new mineral species and named the gemstone after the location where it was found. There's no commercial mining of this gemstone any more, but the current owner of the (now) Capistrano Mining Co., Dave Schreiner still finds good quality gemstones.

In May 2008 the entire region around the mine was closed by the EPA for a study on effects of asbestos (also found in the area). In 2009, Dave began hauling material from the mine to a screening site on Old Camp Road where he allows gemstone hunters to search for stones for a fee. As of January 2016, he had just deposited 30 dump truck loads of new material. The site is only open on weekends. Call Dave at 559-935-5909 for hours, directions, and fees.

This photo is of the screening yard.

California State Symbols - State Fossil Sabre-Tooth Cat

This month I'm covering California's state rocks and fossil and I'm starting with the state fossil - the sabre-tooth cat. This artist's rendition is of a Smilodon californicus, a.k.a. a saber tooth tiger.

Sabre-tooth cats were found all over the world from the Eocene epoch through the end of the Pleistocene epoch about 10,000 years ago. Over a 42 million year period, saber like teeth developed independently in several species of felids - none of which are related to modern cats. The saber teeth were up to 19.7 inches long. Even cubs had saber canines which they shed at about 20 months and then over the next year or so, grew their "big cat" sabers. Of all the species of sabre-tooth cats that existed, the Smilodon is the best known and was the last one to exist. Found throughout North and South America, over 2000 of these animals have been found in California's La Brea Tar Pits. This pic is of the tar pits.

The Smilodon or saber-tooth tiger fossils are so plentiful at La Brea that researchers have been able to determine quite a bit about them. Smilodon was about a foot shorter than a modern day lion, but was about twice as heavy. He had a bobtail so he was likely an ambush predator. Smilodons lived in social groups like lions. Fossil evidence indicates that the group even took care of injured members. Smilodon roared like a lion and because of the big teeth, probably drooled like a St. Bernard. This complete skeleton was found in 1880 and is from the Cleveland Museum of Natural History.

 

Scientists are not sure about the functional advantage of the sabers but several theories have been put forward. One theory is that the cats used the long canines to stab prey repeatedly in the belly or organs. Another is that the long teeth allowed for deep enough bites to kill mega-herbivores. Others postulate that Smilodon probably had a weak jaw and would have been unable to bring down huge animals. This skull with saber canines is from the La Brea Tar Pits.

Rockhounding in Arkansas

There are lots of other rocks to find in Arkansas.  The Rockhounding Arkansas website divides the state into five regions for rockhounding and fossil collection.  The Ouachita Mountains area has been discussed in the previous posts, so I'll share a little information about the other regions.

The Ozarks Plateau  has wavellite (nice dark green specimens) near Avant on Dug Hill.  Apparently, this hill has been dug so often that it is pitted.  The state filled in and planted Dug Hill a while back but you can still search there for specimens as long as it is not for commercial use.  You can also find wavellite in the Montgomery County quarry.  The Plateau also offers many fossils including cinoids, sharks teeth, blatoids, coral and mollusks. This picture is of dark green Arkansas wavellite.  Picture is from RockhoundingArkansas.com

The Arkansas River Valley region has many plant fossils throughout the area.

The West Gulf Coastal Plain has fossil mollusk shells, dinosaur bones, and petrified wood.

The Mississippi Embayment has shark and fish teeth fossils as well as petrified wood and dinosaur bones.

Arkansas State Symbols - State Rock Bauxite

To finish Arkansas, I'll share a little information about their state rock bauxite. Bauxite is the source ore for making aluminum, and Arkansas had lots of this important ore in the center of the state - there is even a town named Bauxite where the mines are. Discovered in the 1890s, bauxite was mined by the General Bauxite Company, then by the Pittsburgh Reduction Company, and finally ( and still) by ALCOA (Aluminum Company of America). Production peaked in Arkansas during the two World Wars, then dropped off as demand was reduced. Bauxite is made up of free silica, silt, various clay minerals, amorphous or crystalline hydrous aluminum oxides, and aluminum hydroxides. Bauxite is also used in the manufacture of abrasives, as a fluxing agent when making steel, and for making high-alumina cements. This photo of bauxite rough is from encyclopediaofarkansas.net.

Mining bauxite is dirty and extracting aluminum from the ore is energy intensive. This is why recycled aluminum is stressed so much - it's takes far less energy to recycle aluminum than to create it from bauxite! Plus, the open pit mines are hazardous. Arkansas, since 1971, has required all open pit mines to be reclaimed once mining is completed. Airports, wildlife habitat, recreation areas, and pastureland have all been created from reclaimed open pit bauxite mines. This photo of an open pit mine is from capturearkansas.com

Arkansas State Symbols - State Mineral Quartz Crystals

The state mineral for Arkansas is the quartz crystal.  Arkansas and Brazil are said to have the highest quality quartz crystals in the world - and many people head to Mt. Ida, a small town in the Ouachita Mountains where most of the quartz crystal mines are located.  Additional mines can be found in Mena, Jessieville and Story.

There are many open pit and tailing piles in the area where you can easily dig through (although you will get very dirty) to find crystals the mine operators missed. There are other locations where you can tap into pockets requiring a pick. You'll still get dirty! These kids are looking for crystals on a tailing pile (Arkansas Dept of Tourism).

 

Most quartz crystal is found in the Ouachita mountains around Hot Springs. This area was sacred to the local Native tribes and the Valley of Vapors (now Hot Springs) was a place of peace even for warring tribes. The crystals were also considered sacred. Now people often use the crystals to "channel." This photo of a channeler crystal is from Wires and Crystals

Arkansas State Symbols - State Gemstone Diamond

You might be able to locate diamonds in other places in Arkansas, but if you are serious  about finding one, you need to go to Crater of Diamonds State Park near Murfreesboro.  This 911 acre park has a 37 acre plowed field over a diamond bearing volcanic pipe - a 95 million year old volcano crater.  The first diamond was found here in 1906 by a farmer.  The site went through numerous owners and attempts to commercially mine diamonds, but there aren't enough stones to make commercial mining profitable.  The site was purchased by the state in 1972.  Since then, the field is plowed every few months and for a small fee (currently $8, 13 and up, $5 under 13) you can search the field for diamonds and other gemstones such as quartz, amethyst, garnet, calcite, jasper, etc.  To date, over 300,000 diamonds have been found. 

The Park is lovely and has a nice pool, campgrounds, a lodge and a visitors' center.

This is a photo of diamonds found at the park, after they were cut and polished. From the Arkansas State Symbols web site.

Rough diamonds don't look like diamonds!  The Park offers video on what to look for.  Dirt doesn't adhere to diamonds, so the best ime to search is a sunny day after a rain.  There are three recommended ways to look for diamonds and other stones in the field:

1) walk slowly, check anything shiny

2) use a frame (about 2 feet square); get down and look closely at aeverthing in the square. After thoroughly searching that square, move the frame to the area right next to the first searched area.  Make a grid as you go.

3) rent a screen at the Park and wash material through it (a seruca) to find stones.

Diamonds found here can be white, yellow and brown.

Most found here are relatively small - and remember if you have them faceted and polished, you will lose some of the stone - but a few large diamonds have been found.  Recently, a woman found a white diamond over 8 carats!

Arizona Rockhounding

Arizonal is also called the Grand Canyon state and has so many rocks, gemstones and minerals it is a rockhound's paradise.  You can find agates, jaspers, meteorites, fossils, rhyolites, malachite, azurite, chrysocolla, native copper, gold, silver, selenite roses (aka Cherokee Tears), aragonite, hematite, various quartzes, etc..  Here are a few of the places you can go look for rocks.  All listed here are public access.  Remeber that Arizona has a day and year limit for collection - 25 pounds per day and 250 pounds per year - and collection cannot be for commercial purposes.  If you want to use rocks commercially, contact the Bureau of Land Management in Arizona to purchase rocks.

In Pima County near Ajo (where there is an open pit copper mine) you can find agates, chalcedony, jaspers, and silicified ironwood (that's another way to say petrified).

From Alpine, go northwest on US260 about 27 miles until you see the sawmills; then go east into the Escudilla Mountains.  You can find lots of moss agates along the north side of the road.

The Apache Power Plant area near Benson has selenite roses and banded rhyolite.

In the Bisbee mine area you can find old mine dumps.  In these, you can locate aragonite, azurite, bornite, calcite, chrysocolla, malachite, native copper and many other minerals and gemstones.  This is a picture of Bisbee azurite.

Between Black Canyon City and Prescott along I-17 are the Bradshaw Mountains.  Placer gold can be found in this area.

Bouse has agates, quartz, and hematite.  On US 72 drive into Bouse, then turn east on Main Street.  Turn right on Rader Road into the hills.  Go about 0.2 miles, then drive between poles on a gravel road.  Go about 0.6 miles then take the left fork.  Go another 0.3 miles and take a second left fork.  Drive another 0.2 miles and park in the green area.

The Burro Creek (famous for lovely jaspers high on the banks) has a Campground about 60 miles northwest of Wickenburg.  The actual campground is about 1.5 miles off US 93. 

The Black Hills Rockhound area has fire agates and other rocks and minerals.  Take highway 70 east out of Safford. Go about 10 miles north on highway 191, then follow the dirt road about 2 miles to the rockhound area.   

The Round Mountain Rockhound area also starts on highway 70 east of Safford.  Drive about 50 miles into New Mexico to just past mile marker 5.  Take the dirt access road and go about 12 miles (back into Arizona).   Follow signs to the rockhound area.

There are many, many more places to look for rocks and fossils in Arizona - my only other suggestion is to go during the winter when the weather is cooler.

 

Arizona State Symbols - State Metal Copper

Arizona's nickname is "The Copper State."  In fact, since 1910, Arizona has been the leading copper producer in the U.S.A.  Although early European settlers knew copper was available, it was difficult to mine and get to market, so they focused on the more lucrative silver and gold ore found in Arizona.  That changed in 1876 when the railroad came through Arizona, making the mining of copper profitable.

Arizona copper mines were initially placer mines or underground mines until about 1917 when the first pit mine opened in Ajo.  Since then, most Arizona copper mines have been pit mines. This photo is of an old placer mine from the Arizona Miner's website.

Copper isn't the only mineral extracted from these mines.  I've discussed the turquoise - which is prized but not a huge prodution area for the state.  The molybdenum, gravel, portland cement, crushed stone and lime are by products of copper mining.  Together with copper, these minerals comprise 99% of Arizona production value and employ over 10,000 people.

Early copper mining extracted ore that was 30% pure yielding 600 pounds of copper per ton of ore mined.  By the 1930s, yield was down to about 4% per ton.  Newer mining techniques mean that Arizona commonly mines ore with a mere 0.35% purity or a yield of 7 pounds or copper per ton of ore mined. This is a photo of native copper.

Copper mining is not without controversy - it is damaging to the environment and the open pit mines are huge and ugly.  Copper mining uses approximatelly 200 gallons of fresh water for every ton of ore mined - and remember that may yield only 7 pounds of copper metal.  This mining reduces air quality for miles away from the actual mine sites.

Further controversy arose in 2015 when one of tohe largest copper sites in the Oak Flat Area east of Phoenix was set to be traded by the federal government to a private company to open the largest copper mine in the U.S.  Native Americans protested that this would destroy a holy site.  Senator John McCaion pushed a bill through Congress granting the trade and opening what is now the largest pit copper mine. Sadly, since the opening of the new mine,metal prices have dropped drastically and copper is much less profitable than it was when the mine was planned.  Below is a picture of an Arizona open pit copper mine near Morenci.

 

 

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