Alaska, California, Colorado, Nevada (notably), New Mexico, and South Dakota.
In
addition to these recoveries by amalgamation and cyanidation, the
rapidly disappearing chlorination process yielded 16,420 fine ounces of
gold in 1912, valued at $339,432, against 181,206 fine ounces in 1911.
The output was 685 ounces from South Carolina and 15,735 ounces from
California in 1912, against 263 ounces from South Carolina, 20,006
ounces from California, and 160,937 ounces from Colorado in 1911.
(There was a very small output by chlorination in Colorado in 1912, but
it is included in the recovery by cyanidation above.)
According
to the percentages of the total output from all sources of gold and
silver, amalgamation yielded 22.3 per cent of the gold and 1.2 per cent
of the silver in 1912, against 23.9 per cent of the gold and 1.54 per
cent of the silver in 1911. Cyanidation yielded 30.9 per cent of the
gold and 17.8 per cent of the silver in 19*12, against 26.1 per cent of
the gold and 14.1 per cent of the silver in 1911. The decrease in
relative output by amalgamation is therefore offset by a corresponding
increased application of the cyanide process. For details of relative
recoveries by States, where interesting differences are exhibited, the
reader is referred to the table above. For details of consumption of
quicksilver in the amalgamation process and of potassium and sodium
cyanide in the cyanide process in many of the Western States, the
reader is referred to the separate mine reports indicated in the
prefatory note. Data as to consumption of these supplies are not yet
sufficiently complete for tabulation for the entire United States.
19373°—m u 1912—vol 1------18
