The discovery of America influenced the market of the precious metals less by the peculiar wealth of the mines in that part of the world than by their almost incredible number.(829) The sources of wealth that the conquistadores first lighted upon were, however, much over-estimated.(830) The production of the American mines first assumed great importance after the discovery of Potosi, in 1545, which was soon followed by the working of the American mines at Guanaxuato. (1558.) Coincident with this was the extraordinary “chance” of Medina’s invention, in 1557; by means of which, it became possible to separate silver from foreign elements by the cool process of amalgamation, instead of melting it as had hitherto been done; an invention all the more important in America, for the reason that in that country, where there is so much rich ore, there is scarcely any fuel, in the neighborhood(831) of where it is found. During the first hundred years the mines of Peru occupied the most prominent place; whereas they were afterwards completely overshadowed by the Mexican.(832) According to Humboldt,(833) the annual export of gold and silver from America to Europe, between 1492 and 1500, amounted to 250,000 piasters; between 1500 and 1545, to 3,000,000;(834) from that time to 1600, to 11,000,000; in the seventeenth century, to about 16,000,000; during the first half the eighteenth century to 22,500,000; during the second half, to 35,300,000. The production of gold in Brazil began to be important after the commencement of the eighteenth century,(835) and the working of the Mexican silver mines of Valencia, Biscaina etc. from the middle of the same century. In the beginning of the nineteenth century, Mexico produced, annually, 537,512 kilogrammes of silver, and 1,609 kilogrammes of gold; Peru, 140,078 and 782 of silver and gold respectively; Buenos Ayres, 110,764 and 506; Chili, 6,827 and 2,807; New Granada, 4,714 kilogrammes of gold; Brazil, 3,700 kilogrammes of gold; the whole of America together, 795,581 kilogrammes of silver and 14,018 kilogrammes of gold, worth about 60,750,000 thalers.(836) During the uprisings between 1810 and 1825, which separated Spanish America from the mother country, the production of the mines diminished as surprisingly as it had increased in the previous generation by reason of the greater liberality of Spanish colonial policy.(837) Since that time, a certain increase has, indeed, been noticed, which, however, had not immediately before the discovery of the gold mines of California by any means attained the height reached in 1808, but only an annual production of 701,570 kilogrammes of silver, and of 15,215 kilogrammes of gold, with an aggregate value of more than 56,000,000 thalers.(838)