in
1909. Of this total, $10,143,780 was derived from siliceous ores,
against $10,433,402 from this source in 1909; $658,288 came from copper
ores against $691,062 in 1909; and $24,577 was from lead ores against
$8,975 in 1909.
The
production of silver in California in 1910 was 1,840,085 fine ounces,
against 2,098,253 fine ounces in 1909. From refining of placer gold was
recovered 41,856 fine ounces, against 40,967 ounces in 1909; from
siliceous (mainly gold-quartz) ores were derived 257,355 ounces,
against 456,826 ounces in 1909; from refining of copper from copper
ores 1,363,668 ounces, against 1,539,665 ounces in 1909; and from
silver-lead ores 177,206 fine ounces, against 60,795 ounces in 1909.
The copper mines of Shasta County produced 1,192,520 ounces of silver
in 1910, against 1,386,817 ounces m 1909, and those of Calaveras County
144,683 ounces, against 119,696 ounces in 1909. Inyo County produced
its entire quantity of silver from silver-lead ores in 1910, and very
much the greater part of it in 1909. From siliceous ores Kern County
produced 64,830 ounces in 1910, against 195,365 ounces in 1909.
Although the greater pmt of the California silver production is from
refining of copper and of gold, there were 4 silver mines producing in
Kern Countv and 5 in San Bernardino County in 1910.
Colorado.—In
1910 the production of gold in Colorado was $20,507,058, a decrease of
$1,482,278 from the output fox 1909. The production of Cripple Creek
decreased $468,420, pending the unwater-mg of the deeper levels by the
Roosevelt drainage tunnel and owing to the unwillingness of operators
to extract ore from great depths at heavy cost for pumping. The output
of Ouray County showed a decrease of $848,978, against an increase of
$1,016,127 in 1909. Notable decreases were recorded in 1910 also from
Lake, Park, Gilpin, and Summit counties, and smaller decreases from
Boulder, Clear Creek, Dolores, and Eagle counties. The production of La
Plata County increased $263,725, that of San Miguel County $209,742,
and that of Gunnison County $125,479 in 1910; and smaller increases
were recorded from Chaffee, Mineral, and San Juan counties. The chief
gold-producing counties of Colorado, with their outputs for 1910, were
Teller (Cripple Creek), with $11,002,253; San Miguel, with $2,494,793;
Ouray, with $2,195,847; and Lake (Leadville), with $1,213,134. Other
important producing counties in 1910 were San Juan, with $710,527;
Gilpin, with $687,902; and Clear Creek, with $522,524. The output of La
Plata Countv was $390,844, of Summit $368,766, and of Park $265,547.
Gunnison County produced $233,972, and Boulder and Mineral counties
each produced over $100,000 in 1910. The San Juan region, including San
Juan, San Miguel, Ouray, Dolores, Hinsdale, Montezuma, and La Plata
counties in southwestern Colorado, produced altogether $5,822,422,
against $6,170,201 in 1909. The Clear Creek region, including Boulder,
Clear Creek, and Gilpin counties, produced $1,350,337, against
$1,586,991 in 1909. Of the total ore tonnage mined, dry or siliceous
ores made up 80.4 per cent and yielded $19,498,099 of the gold, or 95
per cent. Placers yielded nearly 2 per cent of the gold, and the
remainder came from lead, copper, zinc, and lead-zinc ores. The total
placer gold production in Colorado in 1910 was $395,465, a decrease of
$63,027. Summit County with 4 dredges and 5 small placers, mainly in
the Breckenridge district, yielded over 88 per cent
