The estimated value of natural gemstones produced from U.S. deposits during 2004 was 12.9 million dollars. This was a 3-percent increase from that of 2003. U.S. gem-stone production included agates, amber, beryl, coral, garnet, jade, jasper, opal, pearl, quartz, sapphire, shell, topaz, tourmaline, turquoise and other gem materials. More than 60 varieties of gemstones have been produced commercially from U.S. mines. But commercial mining of gemstones has never been extensively undertaken in the United States. Most of the deposits have been relatively small compared with other mining operations. In the United States, much of the current gem-stone mining is conducted by collectors, gem clubs and hobbyists rather than business organizations.
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