Aquamarine and other beryl gems.—Beryl
gems have been obtained intermittently from many localities, prominent
among which are Stoneham and other localities in Maine; Royalston,
Mass.; Merryall, Conn.; Alexander, Mitchell, Yancey, and Macon
counties, N. C; Mount Antero, Chaffee County, Colo.; Riverside and San
Diego counties, Cal. The localities are scattered and mining and
prospecting have been irregular.
Garnet.—The
"Arizona ruby" or garnet from the Navajo Indian Reservation has
supplied the gem trade with varying quantities of fine garnet to the
present time. Mason branch in Macon County, N. C, yielding the
rose-pink rhodoite garnet, was an important source of gem garnet from
1897 to 1901. The majority of other gem garnets have been obtained from
numerous localities and chiefly during mining for other minerals.
Noteworthy among these was the hyacinth or spessartite variety from
Amelia, Va., and from San Diego County, Cal.
Tourmaline.—Tourmaline
has been obtained intermittently but not in large quantities from
several localities in Maine and Connecticut. After 1900 the deposits
of southern California became large producers and were actively worked
for several years. Since 1911 only a few of these mines have been
systematically worked, and the production has not been large. In
connection with tourmaline mining in southern California lilac to
rose-colored spodumene, called "kunzite" and "California iris," has
been obtained in quantity and has taken an important place among
American gems.
Chrysoprase.—Chrysoprase
was first found near Riddle, Oreg., in 1884. In 1887 deposits were
discovered in Tulare County, Cal. There was only a small annual
production for a number of years, but between 1901 and 1911 the output
was large.
Quartz.—Fine
quartz crystals have been obtained from mines worked for tourmaline and
other gem minerals in various parts of the country. One of the most
important finds was of a lot of large clear crystals on Mokelumne Hill,
Calaveras County, Cal., in 1898. One of these crystals yielded a
flawless sphere 5J inches in diameter.
Amethyst.—Amethyst
has been mined in some quantity in Georgia, North Carolina, and
Virginia, and small outputs have come from numerous other deposits in
these and other States.
Agate.—Agate
has been obtained from most of the Western States, and in some years
the production has been large. The moss agates of Montana and Wyoming
continue to be of importance because of their beauty and of the
quantity in which they are found.
Jasper.—The
varieties of jasper suitable for ornamental purposes known in the
United States have increased greatly. Among the promising varieties are
bloodstone from the Death Valley region, California, and kinradite or
spherulitic quartz and associated jaspers of the San Francisco region.
