More than three-fourths of the silver obtained from America is extricated from the ore by means of quicksilver, the loss of which, in the process of amalgamation, is immense. The quantity that used to be consumed annually in Mexico alone, was about sixteen thousand quintals; and in the whole of South America, about twenty-five thousand quintals were yearly expended, the cost of which there, has been estimated at more than a million dollars. The greater part of this quicksilver, in later years, was furnished by the mine of Almaden in Spain, and that of Istria in Carniola, the celebrated quicksilver mine of Huancavelica in Peru, having greatly fallen off in its produce since the sixteenth century, when it was highly flourishing. The prosperity of the silver mines, both in Mexico and Peru, therefore depended very much on the supplies of quicksilver from Spain, Germany and Italy; for such was the abundance of the ore in those provinces, that apparently the only limit to the amount of silver obtained there, was the want of mercury for amalgamation. In taking a general view of the riches of the other portions of America, Humboldt, who has supplied these details, remarks that, in Peru, silver ore exists in as great abundance as in Mexico, the mines of Lauricocha being capable of yielding as great a produce as those of Guanaxuato; but that the art of mining, and the methods of separating the silver from its ore, are still more defective than in Mexico. Notwithstanding this imperfect system, the total amount of the precious metals annually furnished by America, was at one time estimated at upward of forty-two million dollars; the gold being in proportion to the silver as one to forty-six. From 1492 to 1803, the quantity of gold and silver extracted from the American mines, was equal in value to five billion, seven hundred and six million, seven hundred thousand dollars; of which immense sum, the portion carried to Europe, including the booty gathered by the conquerors of America, is estimated at five billion, four hundred and forty-five million dollars, averaging seventeen million and a half of dollars yearly. The annual importation up to 1803, being divided into six periods, appears to have constantly augmented, and in the following progressive ratio. From 1492 to 1500, it did not exceed two hundred and fifty thousand dollars. From 1500 to 1545, it amounted to three millions of dollars. From 1545 to 1600, to eleven millions. From 1600 to 1700, to sixteen millions. From 1700 to 1750, to twenty-two millions and a half. And, lastly, from 1750 to 1803, to the prodigious sum of thirty-five million, three hundred thousand dollars.