Placer-gold
production from all sources in California in 1911 was $8,986,527,
against $8,888,795 in 1910. Of the placer output for 1911, $675,486 was
derived from 169 hydraulic mines, $7,666,461 from 65 dredges, $479,900
from 141 drift mines, and $164,680 from 210 surface or sluicing mines.
The
total gold output from California deep mines in 1911, was $10,-752,381,
against $10,826,645 in 1910. Of this total $10,317,794 came from
siliceous or gold-quartz ores; $427,789 was derived from the smelting
of copper ores; and $6,798 was from silver-lead ores.
By
counties, the largest gold increases in 1911 were, $477,858 from
Tuolumne, whose output is mainly from deep mines on the Mother Lode;
$415,952 from Sacramento, in which is the important Folsom dredging
field; $186,149 from Amador, another Mother Lode county; $166,436 from
Inyo; $149,478 from Sierra; and $142,306 from Trinity. The largest
decreases were, $413,134 from Shasta, due mainly to copper-smelting
difficulties; $334,336 from Nevada, from both deep and placer mines;
$207,201 from Yuba, mainly from the dredging fields; $174,492 from
Mono; $164,395 from Butte, mainly from dredging; and $145 048 from
Mariposa, on the Mother Lode. Counties producing over $1,000,000 in
gold in California in 1911 were Yuba, with $2,997,072; Amador, with
$2,832,395; Butte, with $2,323,396; Nevada, with $2,199,147;
Sacramento, with $1,812,826; Calaveras, with $1,112,315; Tuolumne, with
$1,093,484; and Shasta, with $1,059,881. Of these Yuba, Butte, and
Sacramento are essentially producers from dredging; Amador, Calaveras,
and Tuolumne are Mother Lode counties; Nevada County production is
mainly from the gold-quartz ores of the Grass Valley district; and
Shasta County produces mainly from siliceous and copper ores.
The
five Mother Lode counties—Amador, Calaveras, Eldorado, Mariposa, and
Tuolumne—whose ores are mostly gold quartz, produced altogether in
1911 gold valued at $4,877,651, against $4,408,990 in 1910 and
$4,821,416 in 1909. The average total gold and silver recovery per ton
from Mother Lode ores in 1911 was $3.57, against $3.78 in 1910.
Silver.—The
production of silver in California in 1911 was 1,270,445 fine ounces,
against 1,840,085 fine ounces in 1910, a decrease of 569,640 ounces. Of
this output the larger part, or 864,397 fine ounces, were recovered in
refining copper produced from California ores. Siliceous ores (mainly
gold quartz) milled and smelted, yielded 291,896 fine ounces, and from
smelting of silver-lead ores was derived 74,611 ounces. From refining
gold bullion from placers 39,541 fine ounces of silver were obtained.
The copper mines of Shasta County produced 706,445 fine ounces of
silver in 1911, against 1,192,520 ounces in 1910, and those of
Calaveras County 107,987 ounces in 1911, against 144,683 ounces in
1910. Eestricted copper mining and smelting in Shasta County, owing to
litigation over the smelter-fume question, was the main cause of
reduced silver yield in the State. Inyo County produced 56,089 ounces
of silver from silver-lead ores, and Mono, San Bernardino, Amador,
Nevada, Inyo, Tuolumne, and Shasta counties each produced over 20,000
ounces from siliceous ores in 1911. Although the greater part of the
silver output of California is derived from copper and gold ores, there
were 11 silver and 33 silver-lead mines producing in California in
1911, mainly in Inyo and San Bernardino counties.
