PLATINUM.
DOMESTIC PRODUCTION. CRUDE PLATINUM.
The
conditions of platinum production in the United States, where the metal
is obtained mainly as a by-product in placer-gold mining, did not
change materially during 1910. The output, though varying
considerably, has been on the whole larger since 1900 than in the
preceding decade. The production of crude platinum in 1910 was 390 troy
ounces, a decrease of 282 ounces compared with the output of 1909; the
reported value in 1910 was $9,507, or $3,296 less than in 1909. The
average price paid was $24.38 per ounce, compared with $19 in 1909.
Crude platinum generally contains iridium, iridosmine, and gold,
besides some remaining black sand. The platinum content of the crude
sand varies considerably, the average being probably about 70 per cent.
The
entire output of crude platinum in the United States is recovered from
placer mines in Oregon and California, which also produce gold. The
production of California in 1910 amounted to 337 troy ounces of crude
platinum, valued at $8,386. Of this, 304 ounces were recovered as a
by-product in dredging operations in Butte, Yuba, and Sacramento
counties; smaller quantities were recovered from river gravels in
Siskiyou and Trinity counties, and a few ounces from workings in beach
sands in Humboldt County.
In
Oregon the principal production reported comes from beach sands near
Port Orford, m Curry County, and near Bullards, in Coos County. The
quantity recovered in 1910 was only 53 troy ounces, valued at $1,121.
No production was reported from the Rambler mine,1
in Wyoming, nor from the deposit recently discovered in southern Nevada
east of Moapa, where a dike of peridotite in schist contains copper
minerals and carries a little platinum,2 as described in Mineral Rources for 1908 and in a recent bulletin of the Survey.