Page images
PDF
EPUB
[blocks in formation]

Real del Monte
(Pachuca)

} 127,000

750萬

[blocks in formation]

1050 Bolaños

230,000

100° 45' to 100° 52/ of west long. 5th. Group (Group of Zimapan) from 20° 40 to 21°30 of north lat. and from 100° 30' to 102°0' of west long. 6th. Group (Group of New Gallicia) from 21° 5' to 22o 30' of north lat. and from 105° 0' to 106° 30' of west long. 7th. Group (Group of Tasco) from 18° 10 to 19° 20 of north lat. and from 101° 30' to 102° 45′ of west long.

8th Group (Group of Oaxaca) from 16° 40′

to 18° 0' of north lat. 1400

and from 98° 15' to

99° 50 of west long., III.

VOL.

1200

[blocks in formation]

{

[blocks in formation]

Mean Produce of the Mines of New Spain, including the Mines of the northern part of New Biscay, and those of Oaxaca, above

Marcs of silver

2,500,000

We shall afterwards compare the produce of the silver mines of Mexico, with that of the different mines of Europe. It will suffice in this place to observe, that the two millions and a half of marcs of silver annually exported from Vera Cruz, are equal to two thirds of the silver annually extracted from the whole globe. The eight groups into which we have divided the mines of New Spain, occupy a surface of 12,000 square leagues, or a tenth of the whole extent of the kingdom. When we look at the immense wealth of a very small number of mines, for example, the mine of Valenciana, and that of Rayas at Guanaxuato, or the principal veins (vetas madres) of Catorce, Zacatecas, and Real del Monte, we easily perceive that more than 1,400,000 marcs of silver are produced in an extent of surface, not equal in size to that of the district of the mines of Freiberg.

If the quantity of silver annually extracted from the mines of Mexico is ten times greater than what is furnished by all the mines of Europe, on the other hand, gold is not much more abundant in New Spain than in Hungary and Transylvania. These two last

countries annually throw into circulation nearly 5,200 marcs; and the gold delivered into the mint of Mexico, only amounts in ordinary years to 7000 marcs. We may reckon that in times of peace, when the want of mercury does not impede the process of amalgamation, the annual produce of New Spain is,

In Silver, 22 millions of Piastres.
In Gold, 1

23

The Mexican gold is for the most part extracted from alluvious grounds, by means of washing. These grounds are common in the province of Sonora, which as we have already observed, may be considered as the Choco of North America. A great deal of gold has been collected among the sands, with which the bottom of the valley of the Rio Hiaqui, to the east of the missions of Tarahumara, are covered. Farther to the north in Pimeria Alta, under the 31° of latitude, grains of native gold (pepitas) have been found of the weight of from five to six pounds. In these desert regions, the incursions of the savage Indians, the excessive price of provisions, and the want of the necessary water for working, are all great obstacles to the extraction of gold.

Another part of the Mexican gold is extracted from the veins, which intersect the

* Vol. ii. p. 299.

mountains of primitive rock. The veins of native gold are most frequent in the province of Oaxaca, either in gneiss or micaceous slate (glimmerschiefer). This last rock is particularly rich in gold, in the celebrated mines of Rio San Antonio. These veins of which the gangue is lacteous quartz, are more than half a metre in thickness†, but their richness is very unequal. They are frequently strangled, and the extraction of gold in the mines of Oaxaca, is in general by no means considerable. The same metal is to be found either pure or mixed with silver ore, in the greatest number of veins which have been wrought in Mexico; and there is scarcely a single silver mine which does not also contain gold. Native gold is frequently found crystallized in écta hedra, lamina, or in a reticulated form, in the silver minerals of the mines of Villalpando and Rayas near Guanaxuato, in those of Sombrero (intendancy of Valladolid), Guarisamey to the west of Durango, and Mezquital in the province of Guadalaxara. The gold of Mezquital is looked upon as the purest, that is to say, as being least alloyed with silver, iron, and copper. The principal vein in the mine of Santa Cruz, at Villalpando, which I visited in the month of September, 1803, is intersected by a great number of small rotten

*1.6 foot. Trans

veins, (hilos del desposorio) of exceeding richness. The argillaceous slime with which these small veins are filled, contains so great a quantity of gold disseminated in impalpable parcels, that the miners are compelled when they leave the mine nearly in a state of nakedness, to bathe themselves in large vessels, to prevent any of the auriferous clay from being carried off by them on their bodies. The silver mineral of Villalpando generally contains only two ounces of gold per load, (carga of 12 arrobas); but it frequently contains even eight or ten ounces per load, or 1% ounces per quintal. It may be of use to mention here that at the Harz, the pyrites of Rammelsberg contain only a 29 millionth part of gold, which is however extracted with profit*.

The District of the mines of Guanaxuato, has furnished according to the registers of the Provincial Treasury†,

[blocks in formation]

From 1766 to 1775 9,044 3,422,414 0.0026

1776-1785 13,254 5,281,214 0.002+

1786-1795 7,376 5,609,356 0.0013
1796--1803 13,356 4,410,553 0. 029

In 38 years

43,080 18,723,537 0.0023

* Brongniart, Mineralogie, T. ii. p. 345.

+ Estado de la Tresoreria principal de Real Hacienda de Guanaxuato, del 21 de Novembre de 1799, (M. S.)

« ՆախորդըՇարունակել »