Bureau of Mines / Minerals yearbook: Metals and minerals 1978-79
Year 1978-79, Volume 1 (1978-1979)
Baskin, G. David
Gem stones, pp. 363-375 ff. PDF (1.3 MB)
363Gem Stones By G. David Baskin' The value of gem stones and mineral specimens produced in the United States during 1978 was estimated to be $8.9 million. Production in 1979 decreased to an estimated $8.2 million. During both years, turquoise production decreased while tourmaline and sapphire production increased. Amateur collectors accounted for much of the activity in many States. Commercial operators produced rough jade, jasper, agate, sapphire, turquoise, opal, and tourmaline, which they sold mainly to wholesale or retail outlets and also to jewelry manufacturers. DOMESTIC PRODUCTION Mines and collectors in 39 States produced gem materials with an estimated value of $1,000 or more in each State in 1978. Nine States supplied 89% of the total value, as follows: Arizona, $4.6 million; Maine, $1 million; Nevada, $1 million; Oregon, $600,000; California, $240,000; Wyoming, $200,000; New Mexico, $180,000; Texas, $170,000; and Washington, $170,000. In 1979, estimated production in Arizona and Oregon decreased to $4 million and $500,000, respectively, while other values remained the same. Park authorities at the Crater of Diamonds Park in Pike County, Ark., reported 120,000 people visited the park in 1978 and found 608 diamonds. The largest was an 8.5carat, brown stone of undetermined value. Most of the stones are off-white to brown; however, yellow, pink, and green stones are also found. During 1979, the park had 85,400 visitors, and 411 diamonds were found. The largest stone found weighed 5.1 carats. The decrease in attendance reflected a general decrease in tourism around the country; however, "dig for fee" operations remained popular. In 1978, new tourmaline pockets were found in the Mt. Mica pegmatites near West Paris, Maine. The green and blue crystals should yield several cut stones up to 100 carats each. Some of the tourmaline from the Dunton Quarry, Oxford County, was used to create miniature sculptures of animal life native to North America. The gem carvings, some made with several colors of Maine tourmaline, were completed in IdarOberstein, the Federal Republic of Germany, and exhibited at national gem shows in the United States.2 In 1979, one of the largest gem tourmaline-bearing cavities ever discovered in the United States was found at Mt. Mica. In San Diego County, Calif., tourmaline is being produced at the reopened Himalaya Mine. The Tourmaline Queen and Pala Chief mines, in the same county, continue to produce fine gem-quality and specimen tourmaline and morganite. Small quantities of rare red beryl crystals are being mined in a rhyolite in the Wah Wah Mountains in Beaver County, Utah. Much of the material is sold as mineral specimens; however, some fine cut stones have been available. The finer stones, none weighing over 3 carats, have sold for $3,000 per carat. In Mitchell County, N.C., a small pocket of emerald was found at the old Crabtree mine. Several of the crystal specimens would yield fair to good cut stones weighing 1 to 1.5 carats. Sapphire mining continued at Yogo Gulch, Mont. The mine is producing some very fine blue stones. Three carats has been the maximum size cut stone available.
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