CALIFORNIA.
The
production of tourmaline in the United States during 1908 reported to
the Survey was greater than during 1907 by 1,160 pounds. This
production came from California, Connecticut, and Maine, the bulk of it
coming from California. In California the principal output was from the
mines of the Mesa Grande region, with a smaller output from the Rincon,
Ramona, and Pala districts. The principal producers reporting from
Mesa Grande were the Himalaya Mining Company and the San Diego
Tourmaline Mining Company. The latter company reports a large
production of green tourmaline, with one perfect stone weighing 55
carats after cutting. A quantity of pink tourmaline was obtained also.
Edward
H. Davis, of Mesa Grande, Cal., states that a large quantity of
tourmaline was purchased in San Diego by Chinese and Japanese agents
during 1908. Principally the checked gem material suitable for cabochon
cutting is purchased for the Orient. It is thought to be used in bead
necklaces with jade by the wealthier classes.
BURMA.
The
production of tourmaline from the ruby mines district of Burma during
1907 amounted to 20 pounds, valued at £293,° a large decrease from that
of 1906, which amounted to 193 pounds, valued at £1,001.
BRAZIL.
A. S. Atkinsonb mentions
tourmaline mining as one of the most important industries of Brazil.
The deposits occur over a largo area extending from Itamarandiba
northeastward to Piauhy River, a branch of the Arassuahy, and thence
west and northwest as far as Boqueirao arid San Antonio das Salinas,
State of Minas Geraes. In the districts of Theophilo Ottoni and
Arassuahy about 800 persons are engaged in tourmaline mining. The gems
occur in granite and pegmatite veins along the river banks, where they
are washed out by the natives in some quantity. At Theophilo Ottoni the
tourmaline occurs in gravel beds under several feet of forest soils.
These deposits are stripped and worked rather systematically. The gems
here are of ordinary bottle-green color, though they are obtained in
such quantity as to pay well. Perfectly transparent green tourmalines
are obtained from the Larangeiras mine at Arassuahy, in the district of
Itinga. A deposit of blue and red tourmaline has been found rather
recently at San Miguel, not far from the Larangeiras mine. So far most
of these tourmalines are badly checked so that only small gems can be
cut from them.
TURQUOISE.
The
production of turquoise in the United States during 1908 was large and
came from New Mexico, Nevada, Arizona, California, and Colorado. The
demand for turquoise matrix was greater than for the higher grade pure
stone, though considerable of the latter was produced along with the
matrix material. The production of turquoise matrix and turquoise
amounted to nearly 15 tons, for which the
o Rec. Geol. Survey India, vol. 37, pt. 1,1908.
b Mining for gems in Brazil: Eng. and Min. Jour., June 19,1909.
