338 PRODUCE OF SILVER AND GOLD. 



CHAP. XXVI. ' Marks of Silver. 



„ — ' , Guanaxiiato, 2.4f;!l,O<>0 



'Ifverfor S^" ^'''^ ^"t«si, 1,515,000 



four years. Zacatecas, 1,205,000 



^ Mexico, 1,055,000 



Diiraniro, 922,000 



Rosario, CWiOOO 



Giiadala.xara,.., 509,000 



Pachuca, 455.000 



Bolanos, 364.000 



Sombrerete 320,000 



Zimapan, 241J.0OO 



Sum for five years, 9,730,000=5,9'J7,<)33 troy pounds. 



Mean pro- The mean produce of the mines of New Spain, in- 



duce, cludinfi; the northern part of New Biscay and those of 



Oaxaca, is estimated at above 1,541,015 troy pounds of 

 silver, — a quantity equal to two thirds of what is 

 aimually extracted from the whole globe, and ten 

 times as much as is furnished by all the mines of 

 Europe. 

 Produce of On the other hand the produce of the Mexican mines 



k'''^''^- in gold is not much greater than those of Hungary and 



Transylvania ; amounting in ordinary years only to 

 4315 troy pounds. In the former it is chieHy extracted 

 from river-deposites by washing. Auriferous alluvia 

 are common in the province of Sonora, and a great deal 

 of gold has been collected among the sands with which 

 the bottom of the valley of the Rio Hiaijui, to the east 

 of the missions of Tarahumara, is covered. Farther to 

 the north, in Pimeria Alta, masses of native gold 

 weighing five or six pounds liave been found. Part of 

 it is also extracted from veins intersecting the primitive 

 mountains. Veins of this metal are most frequent in 

 the province of Oaxaca, in gneiss and mica-slate. The 

 last rock is particularly rich in the mines of Rio San 

 Antonio. Gold is also found pure, or mixed with 

 silver-ore, in most of those which have been wrought in 

 Mexico. 



The silver sui)plicd by the Mexican veins is extracted 

 from a great variety of minerals. Most of it is obtained 

 from sulphuretted silver, arsenical gray-copper, muriate 



