ivi INTRODUCTION. 



$500,000; Missouri, HiU, $200,000; the Fellows, $1,000,000; Norambagua, 

 $80,000; Gold Hill, $4,000,000; Union Hill $U, 000; Empire, $1,300,000; 

 Hueston Hill, $1,000,000 ; Osborne Hill, $1,000,000 ; Lone Jack, $500,000 ; 

 Gold Tunnel, $1,000,000; Nevada, $400,000; Sneath & Clay, $300,000; 

 Lecompton, §250,000; Wigham, $200,000, and Banner, $200,000. 



The Sierra Buttes yielded $224,000 gross, and $154,000 net, in 1866; 

 and has three years' supply of ore in sight. This mine has paid more 

 regularly than any other in the State, and if the milling capacity were 

 increased, could be made to surpass any other mine in the State in yield. 

 The Independence, on the same vein, yielded $100,000, in 1866, and has 

 ore in sight to last three years. The Primrose, two miles distant, has 

 yielded $226,000— idle. The Union, one mile from Alleghany, yielded 

 $75,000 in a pocket. 



In Plumas County, the Eureka has yielded $1,600,000; the Mammoth, 

 $1,000,000; the Crescent, $500,000; and the Whitney, $68,000. 



In Yuba County, at Brown's Valley, twelve miles from Marysville, and 

 not more than 300 feet above the level of the sea, are the Pennsylvania, 

 which yields 1,000 tons and $10,000 net per month ; the Jefferson, which 

 has paid $250,000 of dividends ; and the Dannebroge, which has yielded 

 $250,000. 



§ 12. Sulphurets. — Most of the quartz mines, and especially the richer 

 ones, have in the rock from one to five per cent, of sulphurets of iron, 

 which contain from $20 to $1,000 per ton of gold. This can not be ob- 

 tained by amalgamation ; and the only resource is to separate the sulphu- 

 rets (the specific gravity of which is 5,) from the pulverized quartz, (the 

 specific gravity of which is 2^). This separation, called concentration, 

 must be done with the assistance of water. The long sluice is now con- 

 sidered the best machine for concentration. The sluice has a grade of 2 

 or 3 inches to 12 feet; and riffles half an inch thick are introduced gradu- 

 ally as the boxes fill up, the sand being occasionally stirred with a hoe. 

 "When the sand is eight inches deep, the riffles are gradually removed one 

 by one, and the sand again stirred up ; and in this way the sulphurets are 

 obtained in a very clean state. The sulphurets are then roasted and put 

 into a chlorine bath. The chlorine unites with the gold ; the chloride of 

 gold is dissolved in water; and the gold is precipitated by sulphate of iron. 

 This process costs usually about $20 per ton, although one superintend- 

 ent says the expense, exclusive of his own supervision, is only $9. The 

 cost of concentration is $10 per ton of sulphurets where the rock contains 

 one per cent. 



