123 



In these regions. The vein of Guanaxuato, the most productive in 

 Mexico, intersects argillaceous and chloritic shale, and porphyry ; it 

 affords one-forth of all the Mexican silver. The Valencia n mine is 

 the richest in Guanaxuato. The Pachuca, Real del Monte, and Moro 

 districts, are near one another. Four great parallel veins tranvers? 

 these districts, through porphyry. 



In the United States the chief silver mines are in California, Ne- 

 vada, Colorado, Utah, Montana, and Idaho. The principal California 

 mines are in its southeastern counties bordering on Nevada, namely : 

 Alpine, Mono, and Inyo ; the total yield in 18 < 4, about $1, 700.000. 

 Those of Nevada are the Washoe region, about Virginia City and the 

 Comstock Lode ; in Lander County, along Reese River Valley, etc., 

 the chief town of which is Austin ; Esmeralda County, southeast of 

 Washoe ; in Eureka County, next east of Lander ; in Lincoln County, 

 the southeastern of the State ; Humboldt County to the north ; White 

 Pine, Nye and Elko counties, east and southeast of Lander County. 

 The rocks connected with the veins in Eastern California and Western 

 Nevada are eruptive rocks, related for the most part to andesyte an 

 part, named propylitei and trachyte, with some doleryte. The mines 

 of Utah, are those of the Big and Little Cottonwood districts (which 

 include the Emma Mine), the American Fork district, the Parley's 

 Park district in the Wahsatch Range north of Big Cottonwood, and 

 the East Tintic district, in whioh are the Eureka Hill mines ; those 

 of Arizona, the Heintzelman, etc.; of Colorado, in the San Juan region; 

 of Northern Michigan, at the copper mines ; of Canada, at Prince's 

 Mine, Spar Island, Lake Superior. 



For the years previous to 1859 the whole yield of silver from United 

 States mines is estimated at $1,000,000. The following are the amounts 

 for the succeeding years, as published in Jones's Senate Report (1877), 

 those for the years 1871 to 1876, inclusive, being from estimates by 

 J. J.Valentine. 



1859 $100,000 



1830 150,000 



1831 2,100,000 



1332 4,500,000 



1333 8,500,000 



1834 11,000,000 



13 .5 11,250,000 



1336 10,000,000 



1837 13,550,000 



1868 £12,000,000 



1869 13,000,000 



1870 17,3 0,000 



1871 19, 86,000 



1872 19,924,429 



1873 27,483,302 



1874 29,699,122 



1875 31,635,-39 



1876 39,292,924 



The Comstock Lode contributed to the silver of the world first in 1861. 

 In 1875 it yielded $14,492,350, and the rest of Nevada $6,717,636- 

 121,209,993 ; and in 18/6 these amounts were 20,570.078 and 7,462,752 

 = $ 8,03;,830. The $7,462,752 from the " rest of Nevada" in 1876, 

 were divided, as follows, between its principal mining regions : Lan- 

 der County, Austin district, $1,187,500 ; Esmeralda County, Columbus 

 district, $1,624,789 ; Elko County, Cornucopia district, $460,048 ; Eu- 

 reka County, $1,480,558 ; Lincoln County, Pioche or Ely district, 

 §790 095 ; Nve County, Tyboe and Reveille districts, $1,450*000. 



The vield in 1876 of Utah was $3,351,5 ; of Colorado, 3,000,000 ; 

 of California, 1,800,000 ; of Arizona, 500,000 ; of Montana, 800,000 ; 

 of Idaho, 300,000 ; of New Mexico, 400,000. 



