Production 1986 1989
Natural $9.3 million $43.0 million[2]
Synthetic 10.3 23.5
$19.6 $66.5
Mine employment 300 800
Imports for consumption: $4.18 billion $5.00 billion
Apparent reliance on imports over 99% 98%
exports[3]
[1]Estimated.
[2]Including freshwater pearls natural, and cultured.
[3]Imports - exports + adjustments for Government and industry stock
changes. Source: _Mineral Commodity Summaries_, 1991, U.S. Bureau of
Mines.
U.S. production of commercial gems includes agate, beryl, freshwater
pearl, garnet, jade, jasper, mother-of-pearl, opal, peridot, quartz,
sapphire, tourmaline, and turquoise.
Except for the few gem diamonds found each year in Arkansas, U.S.
diamond production is very low.
Yet exploration for diamonds continues in Alaska, Colorado, Michigan,
Minnesota, Wisconsin, and Wyoming. A diamond mining project at the
Crater of Diamonds State Park in Arkansas is still being evaluated by
the State.
World diamond reserves are estimated to be about 300 million carats,
including near-gem materials but not diamonds of abrasive quality.
Most of the reserves are in southern Africa, Siberia, and western
Australia. It is difficult to estimate reserves because the value of a
given deposit varies with the market for the gems.
[Illustration: Jade nephrite, China.]
[Illustration: The Hope Diamond, India.]