Potosi mines

Fortunately, for our purposes, the silver from Potosi has a characteristically low level of gold impurity which allows it to be differentiated clearly from the Mexican-European silver stock. As shown in Figure 7 (27), silver from this latter stock was used in Spain, Barcelona, and France, before 1570-1580, when the Potosi mine began to be exploited on a large scale and its yields shipped to Spain. 

The Rio Pilcomayo is a major river that originates in Bolivia and forms part of the boundary between Paraguay and Argentina. The water and sediments in the river are substantially contaminated with arsenic from the Potosi mines in Bolivia (Hudson-Edwards et al., 2001), 245. The arsenic content of Rio Pilcomayo actually increases from 65 pg L-1 at 10.2km downstream from the mines to 100 pg L-1 at about 151 km downstream (Hudson-Edwards et al., 2001), 240, 244. The arsenic increase may be due to a decrease in pH (from 10.3 to 8.42), increased oxidation of the river sediment, and increased activity of sulfide-oxidizing bacteria (Hudson-Edwards et al., 2001), 244-245. 

The American cordillera extending from Alaska to BoUvia has been the most productive source of silver wherever it is associated with Tertiary age intmsive volcanic rocks, mosdy concentrated by hydrothermal action. The largest producing mine in the cordillera is at Potosi, BoUvia, where the total silver output since the 1500s is estimated at over 31,000 metric tons. 

The silver mines of Charcas, Peru, were discovered in 1535, those of Potosi, Peru (now part of Bolivia), in 1545, those of Zacatecas, Mexico, in 1548, and those of Guanajuato, Mexico, in 1550 (108). The first coins struck in America were produced in Mexico in 1536 under the viceroy-ship of Antonio de Mendoza. They were of copper and silver (108). 

According to Father de Acosta, the chief places of the Indies from which they draw silver are New Spaine [Mexico] and Peru but the mines of Peru fan-e surpasse the rest and amongst all others of the worlde, those of Potosi [now in Bolivia] (45). 

Huanca and Villarroel became joint owners of the mines of Potosi, The King of Spain claimed one-fifth of their proceeds (45). 

In the seventeenth century, Father Alvaro Alonso Barba of Potosi said that some of the mines there had been worked by the Incas and that, since the coming of the Spaniards, the wealth of this hill had been distributed to all parts of the world (46). 

Color Plate 14. Hydroxylapatite, Molina Mine, Potosi, Bolivia. Concentric zoning with cores Mn -activated exterior Eu -activated. 50 mm crystals. MWUV. 

P. Alfaro and S. Castro, The Zinc Refinery of IMMSA in San Luis Potosi, Mexico , Zinc and Lead Processing. J.E. Dutrizac, J.A. Gonzalez, G.L. Bolton, P. Hanckock, Eds., Canadian Institute Mining, Metallurgy and Petroleum, Montreal, Canada, 1998, 71-83. 

Colonization led to the discovery of large silver deposits in South and Central America. From the middle of the 16 to the beginning of the 19 century, a quantity of about 100 000 tonnes of silver was transferred from America to Europe. One of the biggest cities of the time grew up near the silver mountain of Potosi in Bolivia. The silver was extracted from the ore with mercury (the method is described in Chapter 5 Gold). In the Huancavelica mine in Peru a high proportion of the native peoples died of mercury poisoning in forced labor. 

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