$38 RESOURCES OF CALIFORNIA. 
CHAPTER VIII. 
MINING. 
$175. Chief Industry —Mining is the chief industry of 
California. It employs more men and pays larger average 
wages, than any other branch of physical labor. Although it 
has been gradually decreasing in the amount of its production, 
in the profits to the individuals engaged in it, and in its rela- 
tive importance in the business of the state, it is yet and will 
long continue to be the largest source of our wealth, and the 
basis to support the other kinds of occupation. 
§ 176. Metals obtainedi—Our mines now wrought are of 
gold, silver, quicksilver, copper, and coal. Ores of tin, lead, 
and antimony in large veins, beds of sulphur, alum, and as- 
phaltum ; lakes of borax and springs of sulphate of magnesia, 
are also found in the state, but they are not wrought at the 
present time, though they will probably all become valuable 
ina few years. Platinum, iridium, and osmium are obtained 
with the gold in some of the placer mines, but are never found 
alone, nor are they ever the main object sought by the miner. 
The annual yield of our gold mines is about forty millions of 
dollars, of our quicksilver two millions of dollars. Our silver, 
copper, and coal mines have been opened within a year, and 
their value is yet unknown. All our other mining is of little 
importance as compared with the gold. 
§177. Gold Mines—Our gold mines are divided into pla- 
cer and quartz. In the former, the metal is found imbedded in 
layers of earthy matter, such as clay, sand, and gravel; in the 
latter it is incased in veins of rock. The methods of mining 
must be adapted to the size of the particles of gold, and the 
