Colorado, 96,076 ounces. The only gains of any size were 663,316 ounces in Nevada and 58,346 ounces in Utah.
Of
the gold-producing States whose output is derived chiefly from milling
ores, Alaska, California, Idaho, and South Dakota still yield more gold
by amalgamation than by cyanidation, but cyanidation produces more gold
than amalgamation in Arizona, Colorado, Montana, Nevada, and Oregon,
and it produces much more silver in Arizona, Colorado, Montana, Nevada,
New Mexico, Oregon, Texas, and Utah. Only in Alaska, California, and
Idaho did the recovery of silver by amalgamation exceed that by
cyanidation. Altogether amalgamation produced gold and silver valued at
$14,294,010 from milling ores in 1920, against $20,258,672 produced by
cyanidation
QUICKSILVER AND POTASSIUM AND SODIUM CYANIDE CONSUMED IN
CERTAIN STATES.
For
details of the consumption of quicksilver in the amalgamation milling
process and of potassium cyanide and sodium cyanide in the cyanidation
process the reader is referred to the mines reports of the several
Western States. The consumption of quicksilver at mills treating ore
and by dredging and other methods of placer mining is given in the
separate chapters on quicksilver in 1917, 1918, 1919, and 1920 in
Mineral Resources.
The following tables were compiled by V. C. Heikes:
Quicksilver consumed in certain Western States, 1916-1920.
