MINING. 2S5 



miles eastward of Sonora, in Tuolumne county, are some rich 

 veins of auriferous quartz, the most prominent of which are 

 the Soulsby and Blakeslee lodes. The Soulsby mill produced 

 forty thousand dollars in three weeks, when it commenced 

 work in 1858, but it has not been so profitable of late. 



§ 214. Silver Mming. — Silver mining has not yet been 

 established fairly as a business in California. The silver ores 

 of Washoe were discovered in 1859, and mining has been 

 fairly commenced there, but the mines of Esmeralda and Coso, 

 w^ithin the limits of tliis state, were not found until the sum- 

 mer of 1860, and up the present time no mills have been 

 established there. 



Silver mining differs much from gold mining. Gold is always 

 found as a metal, never as an ore, and the separation from the 

 accompanying vein-stone with which it is mixed mechanically, is 

 much more simple and easy than the reduction of the ar^entif- 

 erous ores in which the silver is chemically combined with 

 base substances, for which it has a strong affinity. Chemical 

 knowledge and chemical processes are more necessary in min- 

 ing for silver than for gold ; and while all auriferous quartz is of 

 the same kind, and may be treated in the same manner, there 

 are many difterent kinds of silver ores, each of which requires 

 a peculiar treatment. The reduction of silver ore costs on an 

 average, from three to five times as much as the reduction of 

 auriferous quartz. 



Tlie silver ore of Esmeralda and Coso is a sulphuret of 

 silver, nearly all the veins having the same material, though the 

 amount of it scattered through the vein-stone difi^ers greatly 

 in difierent lodes. In some veins there is much free gold, that 

 is, little specks of metalHc gold which can be -separated from 

 the other material in the same manner that gold is separated 

 from auriferous quartz. The methods of reducing silver ore 

 are so numerous and complex, and vary so much in difterent 

 districts and imder different circumstances, that it is impossi- 

 ble to know now what process will be used in Esmeralda and 

 Coso, the resources of which places have been so little studied. 



