Sunstone from Oregon
The United States is one of the main consumers of colored gemstones in the world, but is not known as a important gemstone producer. This was not always the case. Back in the first decade of the 20th century, the US was the leading tourmaline producer in the world, with important mines in Maine and California.
Commercial gemstone mining is still active in 8 different states in the US. Surprisingly, the top state based on total value produced is Tennessee. This is because the American Pearl Company operates the only freshwater pearl farm in the country in Tennessee.
Watermelon Crystal from California
The second most important state in commercial gemstone mining is Arizona, with significant deposits of peridot and turquoise. Arizona is also known for agate, jasper, petrified wood, garnet and opal. Turquoise is the most valuable gemstone produced in Arizona, though production is labor intensive because careful hand extraction is required.
Oregon is internationally famous for its sunstone, a feldspar mineral. Sunstone is a type of labradorite that contains large numbers of microscopic copper platelets that produce an interesting play of color. Oregon also produces a variety of agate, jasper, and obsidian.
Tourmaline was discovered in California at the end of the nineteenth century, and between 1898 and 1914 the Himalaya Mine in San Diego County was the world's largest producer of tourmaline. Turquoise production also has a long history in California, especially in San Bernardino County, but the deposits are no longer active. There are still tourmaline reserves in California, but the cost of mining tourmaline has become prohibitively high.
Most of the gemstones found in the US are in the west, and Idaho, Montana and Nevada have produced notable stones. Idaho produces small quantities of relatively many gem varieties, including agate, jasper, garnet and opal. Idaho is well-known as a source for the rare star garnet. Montana is famed for its sapphires from Yogo Gulch. A range of colors are found, including blue, green, pink, purple, yellow and orange. Nevada at once time produced fine turquoise but recent gem production has mainly been opals from Virgin Valley.
|Peridot Rough from Arizona
||Sapphire Rough from Montana
Arkansas is noted for its quartz, especially rock crystal which is produced and sold as mineral specimens and also for faceted stones, beads, carvings, spheres and other decorative items.