a Small production included under "miscellaneous gems."
6 Includes apatite, calamine;
chloarstrolite, crocidolite, datolite, fossil coral, Iceland spar,
kyanite, lazu-rite, obsidian, peridot, phenacite, rutile, smithsonite,
spodumene (kuuzite), staurolite, thomsonite, titanite, and zircon.
c
Includes chlorastrolite, datolite, epidote, fossil coral, hematite,
kyanite, lazulite, rhodonite, rutile, sepiolite, serpentine, spodumene,
staurolite, and vesuvianite.
d Includes
andalusite, chlorastrolite, datolite, epidote, feldspar, fossil coral,
hematite, Iceland spar, lapis lazuli, obsidian, peridot, phenacite,
pynte, rhodonite, rutile, sepiolite, smithsonite, spodumene,
staurolite, thomsonite, willemite, and zoisite.
The
value given in the tahle largely represents the value of the rough
material; the value of the cut and polished gems is several times
greater. The completeness arid accuracy of the statistics of production
depend on the assistance rendered by the gem miners and dealers, and
their help is greatly appreciated. The Geological Survey carries on a
large correspondence concerning precious stones, and
1The
table giving statistics of the value of the gems and precious stones
produced In 1917 was compiled by Miss Blanche U. Stoddard.
77740°—M R 1917, pt 2------10
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