284 RESOURCES OF CALIFORNIA. 



§ 212. SuljoJiurets. — Many auriferous quartz veins contain 

 considerable quantities of sulphurets or pyrites of iron, cop- 

 per and lead, and their presence prevents amalgamation, and 

 thus causes a great loss of gold. It is said that on some occa- 

 sions in good mills, not more than twenty or thirty dollars 

 have been obtained from a ton of vein-stone which had seven 

 or eight hundred dollars of gold in every ton. The best 

 method of treating the quartz containing pyrites, is to roast it, 

 and thus drive ofl* the sulphur, but this j^rocess is so expensive 

 that it is seldom used ; and the common practice is to crush 

 and amalgamate the rock, and save the concentrated tailings for 

 some future time, when there may be a sale for them, or when 

 it will be cheaper to reduce them. The pulverized sulphurets 

 are decomposed by exposure to the air, and after the tailings 

 have been preserved for a time, they may pay better at the 

 second amalgamation than at the first. A mixture of common 

 salt assists the decomposition of the pyrites. 



§ 213. Chief Quartz-Mills. — The most productive quartz- 

 mill in the state is the Benton mill, on Fremont's Ranch, in 

 Mariposa county. It is also the largest, having fortj^-eight 

 stamps. There are four mills on the estate, with ninety-one 

 stamps in all, and their average yield per month is sixty thou- 

 sand dollars. A railroad four miles long conveys the quartz 

 from the lode to the mills. The Allison quartz mine in ]N'evada 

 county produces forty thousand dollars per month. The Sierra 

 Buttes quartz-mill, twelve miles from Downieville, yields about 

 fifteen thousand dollars per month. These last mills run 

 night and day, and crush and amalgamate ten thousand tons 

 of rock a year or twenty-eight tons per day. Forty men are 

 employed, twenty-five to quarry the rock, five in the mill to 

 attend to the stamps and amalgamation, one to do carpentry, 

 one for blacksmithing, and eight for getting out timber, trans- 

 porting quartz, and so forth. The cost of quarrying, crush- 

 ing, and amalgamating a ton of rock is six dollars. The wages 

 of the men are from fifty to seventy dollars per month with 

 boarding. The average wages is sixty dollars. About ten 



