342 RESOURCES OP CALIFORNIA. 



seldom found in Calfornia of late years, but from 1849 to 

 1853 it was a common event to find pieces of five or ten 

 pounds. The largest nugget on record was found at Ballarat, 

 Australia, in 1855, and weighed 224 pounds Troy; and in 1854, 

 a piece of gold containing some quartz, and weighing 195 

 pounds Troy, was found in Calaveras County, California. 



268. Silver. Extensive deposits of silver ore occur east 

 of the Sierra Nevada, in the basins of Owen Lake and the 

 Mojave and Colorado Rivers ; but the only silver mines of note 

 in the State are those of argentiferous galena at Cerro Gordo. 



269. Quicksilver. Quicksilver is one of the leading met- 

 als of California in industrial value, its total yield surpassing 

 that of silver obtained from the argentiferous lead added to 

 that separated from gold. Mercury occurs in its metallic form 

 in some porous rocks near St. Helena, from which it can be 

 shaken out ; but the market is supplied by mines of sulphuret 

 or cinnabar, the richest deposits of which are at New Alma- 

 den, New Idria, Knoxville, Pope Valley, Vallejo, and various 

 places in Sonoma County. Cinnabar is found at many points 

 in the cretaceous rocks of the Coast Range, from Santa Bar- 

 bara to Shasta. 



270. Platina. Platina, iridium, and osmium, are three 

 white metals resembling steel, often found in the placer mines 

 of California. They usually occur together, and are found 

 more abundantly in the lower part of the Klamath Valley than 

 in any other part of the State. In many districts they are en- 

 tirely lacking. Platina is found in lumps by itself; iridium 

 and osmium are found united, and are then called irid-osmium. 

 These metals are found in small particles, usually fine scales ; 

 the largest piece was of irid-osmium, found on the Lower 

 Klamath, and weighed an ounce and a quarter. They are not 

 found separate from the gold, nor are they ever the main 

 object of search ; they are obtained in small quantities only, 

 and are rarely bought and sold in the State ; they have no 

 fixed market price. When mixed with gold dust, they in- 



