62 RESOURCES OF CALIFORNIA. 
The gangue or vein-stone is quartz. The ore varies in rich- 
ness from 5 to 70 per cent.: the ore of the Almaden mine 
averages 18 per cent.; that of the Enriqueta mine is about the 
same; that of the New Idria mine is about 8 per cent. The 
lodes are extremely irregular; sometimes there will be a mere 
thread, which will widen out into a mass forty feet in breadth, 
twenty high, and seventy long, of rich ore, and then diminish 
again to a thread. The total annual production of the state 
will probably amount to three million seven hundred thousand 
pounds, of which two million four hundred thousand at least 
will come from New Almaden. The New Idria mines, in the 
Coast Mountains, about seventy-five miles southeastward from 
San José, furnish about three hundred and fifty thousand 
pounds per annum. In Napa county, on the slopes of Mount St. 
Helena, and in Sonoma county, in the Geyser Mountains, west 
of Clear Lake, cinnabar has been found, and companies are 
now at work opening the mines. Whether they will prove to 
be of value is as yet a matter of doubt. It is a singular fea- 
ture of the cinnabar veins in these two last-mentioned places, 
that they are accompanied by a porous limestone which is full 
of pure quicksilver ; and when the stone is shaken or struck, 
the liquid metal flies out in minute globules. There have been 
rumors of discoveries of cinnabar in other parts of the state, 
but they are not well authenticated. 
§ 43. Copper.—Copper ore has been found near Crescent 
City ; at Copper Cajfion, in the southwestern corner of Calave- 
ras county; in San Diego county; in Napa county; six miles 
below Grizzly Flat, in El Dorado county; near Sweetland, in 
Nevada county; and in Shasta county. Sulphuret of copper, 
or copper pyrites, is found in auriferous quartz-lodes in nearly 
all the minjng counties. Near Sweetland, Nevada county, 
there is a claim in which so much copper is found with the 
gold, that the dust is worth only eleven dollars per ounce. 
No copper has been smelted in the state; the only attempts 
to mine for the ore have been at Copper Cafion, and on the 
bank of the Cosumnes River, below Grizzly Flat. Some of 
