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gions * ; but this learned traveller appears to have forgot, that in Peru the richest provinces in gold are the partidos of Pataz and Huailas, which are on the ridge of the Cordilleras. The Incas drew immense quantities of gold from the plains of Curimayo' to the north-east of the town of Caxamarca, at more than 3,400 metres t of elevation. It has also been extracted from the right bank of the Rio de Micuipampa, between the Cerro de San Jose, and the plain called by the natives Choropampa, or plain of shells, on account

enormous quantity of oysters, cardia, and other petrifications of marine shells, contained in the formation of alpine limestone of Gualgayoc. Considerable masses of gold have been found there, disseminated in branches and filaments, in veins of red and vitreous silver, at more than 4000 metres of elevation above the level of the ocean. As to the alluvial ground in which the gold stream-works of Choco are established, and those of la Soñora and Brazil, are we to be surprised to find them rather at the bottom than on the summits of mountains ? If tin S appears an exception to this law of nature,

of an

* Ulloa, Noticias Americanas. 1772, p. 223 and 236.
+ 11,154 feet. Trans.
$ 13,123 feet. Trans.

For instance, the tin of the stream-works (Wasch-zinn), on the summit of the Fichtelgebirge.

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it is undoubtedly because the granitic beds, in which it was originally contained, have been decomposed in their place.

The process of amalgamation of silver minerals followed in Peru, since 1571, is the same as that which is used in Mexico. In the two countries the schlich is manufactured according to the rules prescribed by Medina, Barba, Corso de Leca and Corrosegarra ; but, generally speaking, amalgamation is practised with more care and intelligence by the Mexican miners at Guanaxuato and Zacatecas, than by the miners of Peru. In New Spain the expence of amalgamation is generally estimated at 87 piastres 4 reals for one hundred quintals of minerals, containing four ounces of silver per quintal, of which sum, 25 piastres go for waste of mercury. As three hundred quintals produce fifty marcs of silver, which, according to the common price of silver * at the mines, are worth 562 piastres, it follows that the expence of amalgamation amounts nearly to 24 per cent. of the value of the silver. But in Peru, where the mercury of

* At 7 piastres, 2 reals. Garces, p. 144. In the beginning of the seventeenth century, the expences of amalgamation at Potosi, for a caxon of ore weighing 5 quintals, and containing 20 marcs of silver, were only estimated at 30 piastres, or 20 per cent. although the pound of mercury cost a piastre. Barba, p. 118.

Huancavelica is generally sold for 60 or 70 piastres the quintal *, the expences amount, in several districts of unines, to 30 or 38 per cent. At the Cerro de Gualgayoc for example, where the price of labour is from three to four 'reals (from 40 to 50 sous) per day, a load of schlich, containing from two to three marcs of silver, costs seven piastres in the process of amalgamation, viz.

swood

In roasting

labour
Muriate of Soda
Lime
Labour in treading the schlich
Consumption of mercury

Reals of silver.

8 2 6 4 12 24

Total 56

During my stay in the Cordillera of the Andes, there were only two districts of mines where the method of M. de Born, of amalgamation in casks, was followed with any degree of success, namely, the Real de Requay, in the province of Huailas, and Tallenga, in the province of Caxatambo. † To judge of the considerable loss of silver annually experienced in

* Campomanes, de la educacion popular, T. ii. p. 132.

+ The mines near Requay, where a German amalgamation work has been constructed, is called Ticapamba, and belongs to Don Juan Ignacio Gamio. The work of Tallenga was established by Don Juan Baptista Arieta.

In the years

Peru from the ignorance of the amalgamators, it is enough to mention the simple fact that it daily happens that an azoguero extracts 15. marcs per caxon, from the same mineral, out of which, hitherto, there has never been extracted more than ten or twelve marcs. which immediately succeeded the discovery of the mines of Yauricocha, they only wrought the pacos or oxides of iron, mixed with native silver, and muriate of silver. The prismatic black silver, and the argentiferous grey copper, were thrown among the rubbish. In the same manner, on building the small town of Micuipampa, walls were constructed of very rich pieces of gangue, and those minerals only which were of a yellowish brown, or of an earthy appearance, like the pacos, were considered as containing silver. These facts will not appear so surprising, when we consider that not more than forty years ago, in one of the most civilized countries of Europe, calamine was employed in the making of roads, without its being perceived that this substance, which was soiled with clay, contained zinc.

II. The Precidentia, or Capitania general of Chili, produces annually, in gold and silver, one million seven hundred thousand piastres. *

* 357,000 Sterling. Trans.

The most considerable mines of gold, are Pe. torca, ten leagues to the South of Chuapa; Yapel or Villa de Cuscus, Llaoin, Tiltil and Ligua, near Quillota. Mines are also wrought in the partidos of Copiapo, Coquimbo and Guasco. The silver mining operations of Chili are in general by no means productive. The Cerro de Uspallata, at eight leagues distance to the north-west of Mendoza, contains, however, pacos so rich that they yield from two to three thousand marcs per chest (caxan) of 5000 pounds, or 40 or 60 marcs of silver per quintal. The produce of the mines of Chili, has considerably increased of late years. In 1790 there was coined at Santiago 721,000 piastres in gold, and 146,000 in silver.

III. The great mass of precious metals, supplied by the viceroyalty of Buenos Ayres, is entirely derived from the most western part, the provincias de la Sierra, which in 1778 were separated from Peru. estimate the annual produce, which is almost wholly silver, at four millions two hundred thousand piastres. * The districts which supply the most are Potosi, Chaganta, Porco t, Oruro,

We may

* 882,0001. Sterling. Trans.

† See Alonzo Barba, Arte de los Metales (ed. 1729) p. 48, respecting the silver mines of Porco, wrought by the Incas.

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