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Danburite vs. Topaz
Uh oh, you got a crystal that is colorless or yellow or pink, that looks like a multisided prism with multi-faceted terminations, and has striations down the length of the crystal. What is it?
If it has a hardenss of 7 to 7.5, a specific gravity of 3.0, fluoresces sky blue under long-wave UV and doesn't cleave very well, you've got Danburite. Danburite is name for Danbury, CT where it was first found, and is mined in Burma, Japan, Russia, Madagascar and San Luis Potosi, Mexico.
If is a little harder (8), a little bit heavier (S.G. = 3.5), doesn't fluoresce well and cleaves perfectly, you've go Topaz.
Brief History of Copper Country
The first wave of eager explorers, Hard-rock miners and adventures stepped off the big lake schooners at Copper Harbor in the 1840s and commenced explore the dream, a fickle mirage of sparking copper, silver and even gold. With picks and shovels they pecked at the land for fabled treasure. They soon discovered that they needed more than a pick n shovel. Some nuggets weighed in at 30 tons and more. Soon miners labored at sinking shafts 400 feet deep in the ore beds that straggled up from Lake Superior and onto the Keweenaw Peninsula.
Major corporate enterprises hauled out tons of precious silver and rich copper. Manufacturers marveled at a copper so pure that it did not need refinement. The Quincy Mine, near Hancock emerged as a critical cog in the Civil War and provided 60% of the copper used by the Union forces for canteens, cannon and ammunition.
Now this Quincy Mine is just North of Hancock, Michigan and part of the Keweenaw National Historical Park. It is open to the public for tours and has the largest steam-powered mine hoist ever built, bringing copper ore from a 9,260 feet on the incline, 5,640 feet vertically. It was built in 1920 and was operated until 1931. The University operates an incline car system that takes you down to one of the lower mine entrances for a tour. This was a great experience for us. They also offer a video of past history of the miners that worked this mine. There was a huge dump area and I got out my Gold Bug and did a little exploring and found a nice piece of a copper fan. You will see this and many pieces of copper that we collected on our trip as we traveled up Highway 26 to Historical Calumet mine district.
Serpintine is made of variety of minerals and has green or red colors in the rock. It's bowenite variety are often used in place of jadeite. Serpentine rock is primarily composed of one or more of the three magnesium silicate minerals: lizardite, chrysotile and antigorite. It can be found in central and northern California, Montana, Cornwall, New Zealand, and Australia.
First found in 3/9/1842 by Francisco Lopez about 35 miles northwest of Los Angeles while digging for wild onions. Gold found at Sutter's Mill in Coloma, CA by James Marshall changed the course of history with the start of the Gold Rush (1848-1855).
Its occrrence is very rare, and often found as veins within rocks, particularly quartz. Gold is a soft precious metal. It has a bright yellow color and hardness of 2.5-3.
In 1985 it was named the official state gem of California. Frist described in 1907 by George D. Louderback, who named it benitoite for its occurrence near the headwaters of the San Benito River, CA. A rare blue barium titanium silicate mineral, found in hydrothermally altered serpentinite. The hardness of benitoite is 6-6.5, and it fluoresces intense blue under shortwave ultraviolet light.
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