122 DESCRIPTIONS OF MINERALS. 



with porphyries. The chlorides and native amalgams are found in 

 regions more toward the coast, while the sulphides and antimonial 

 ores abound nearer the Cordilleras. The richest mines are not far dis- 

 tant from Copiapo, in the mountains north of the valley of Huasco. 

 The mines of Mt. Chanarcillo, about 16 leagues south, of Copiapo, 

 abound in horn silver, and begin to yield arsenio-sulphides at a depth, 

 of about 500 feet. The mines of Punta Brava, which are nearer the 

 Cordilleras, afford the arsenical and antimonial ores. 



In Peru, the principal mines are in the districts of Pasco, Chota, and 

 Huantava. Those of Pasco are 15,700 feet above the sea, while those 

 of Huantava are in a low desert plain, near the port of Yquique, in the 

 southern part of Peru. The ores afforded are the same as in Chili. 

 The mines of Huantava are noted for the large masses of native silver 

 they have afforded. Silver is obtained in Peru, also, in the districts of 

 Caxamarca, Pataz, Huamanchuco, and Hualgayoc. 



The Potosi mines in Bolivia, occur in a mountain of argillaceous 

 shale, whose summit is covered by a bed of argillaceous porphyry. 

 The ore is the ruby silver, and argentite with native silver. The 'dis- 

 trict of Caracoles, between Chili and Bolivia, yields much silver. 



In Europe the principal mines are those of Spain, the province of 

 Guadalajara, where the ore is chiefly freieslebenite ; of Kongsberg in 

 Norway ; of Saxony, chiefly at Freiberg ; the Hartz ; in Austria, Hun- 

 gary, Transylvania, and the Banat ; and Russia. The mines of Kongs- 

 berg occur in gneiss and hornblende slate, in a gangue of calc spar. 

 They were especially rich in native silver. 



Tile mines of Saxony occur mostly in gneiss, in the vicinity of Frei- 

 berg, Ehrenfriedensdorf, Johanngeorgenstadt, Annaberg, and. Schnee- 

 berg. 



The ores of .the Hartz are mostly argentiferous copper pyrites and 

 galena, yet the ruby silver, argentite, stephanite, occur, especially at 

 Andreaskreutz, and the mines of that vicinity. The rock intersected 

 by the deposits is mostly an argillaceous shale. Calcite is the usual 

 gangue, though it is sometimes quartz. 



In the Tyrol, Austria, argentite, argentiferous tetrahedrite, and mis- 

 pickel occur in a gangue of quartz, in argillaceous schist. The Hun- 

 garian mines at Schemnitz and Kremnitz, occur in syenyte and horn- 

 blende porphyry, in a gangue of quartz, often with calcite or barite 

 (heavy spar>, and sometimes fluorite. The ores are argentite tetrahe- 

 drite, galena, blende, pyritous copper and iron ; and the galena and 

 copper ores are argentiferous. France produces some silver from ar- 

 gentiferous galena at Huelgoet in Brittany, and the mines of Pcntgi- 

 baud, Puy-de-Dome. 



The Russian mines are in Kolyvan in the Altai, and Xertchinsk in 

 the Daouria Mountains, Siberia (east of Lake BaikaP. The Daouria 

 mines afford an argentiferous galena which is worked for its silver ; 

 it occurs in a crystalline limestone. The silver ores of the Altai occur 

 in Silurian schists in the vicinity of porphyry, which contain also 

 gold, copper, and lead ores. 



The mines of Mexico are most abundant between 18° and 24° north 

 latitude, on the back or sides of the Cordilleras, and especially the 

 west side ; and the principal are those of the districts of Guanaxuato. 

 Zacatecas, Fresnillo, Sombrerete, Catorce, Oaxaca, Pachuca, Rea 1 del 

 Monte, Batopilas, and Tasco. The veins traverse very different racks 



