tonnage
mined. The tonnages of zinc ores of New Jersey and Virginia are also
omitted, as these produce no silver or gold. With the exceptions noted
the total tonnage treated or sold, of crude ore and old slags and
tailings, that produced gold and silver in 1910, was 30,287,175 short
tons. Of this quantity 8,528,596 tons were treated in gold and silver
mills, producing 2,366,322 fine ounces of gold and 8,245,851 fine
ounces of silver as mill bullion; 15,407,517 tons were sent to straight
concentrating mills, producing (with a portion of the tonnage treated
in gold and silver mills) 2,597,992 tons of concentrates containing,
in addition to copper, lead, or zinc, 475,452 fine ounces of
recoverable gold and 19,949,379 fine ounces of silver; 6,016,425 short
tons were sent to smelters to be smelted crude and contained 623,272
fine ounces of gold and 28,487,837 ounces of silver; and 334,637 tons
were of old slags, tailings, smelter cleanings, etc., sold or treated,
and contained 30,323 ounces of gold and 333,809 ounces of silver. The
relatively large proportion of gold recovered in the mills and the
relatively larger proportion of silver recovered by smelting are
notable.
In
the table given Utah ranks first in point of total tonnage, the bulk of
which was concentrated, and the greater portion of the gold and silver
of which was recovered by the smelters, either from concentrates or
crude ores. Montana ranks second and Arizona third in tonnage given,
with the recovery again mainly by the smelters. In quantity of crude
ore sent direct to smelters Arizona ranks first. In quantity of ore
treated at gold and silver mills California ranks first, followed in
order by South Dakota, Alaska, and Colorado, these being represented,
respectively, mainly by the mines and mills of the great Mother Lode,
Grass Valley, ilomestake, Treadwell, and Cripple Creek.
