Mr. Fletcher, who has lived a long time in Cerro Pasco, says that a purchaser of the ores (making sure of his "guias" or experiments on the yield of the ore) can count his gains as easily and certainly as he can the dollars in his pocket; that those men who lose are either the lazy and the careless, or the speculators and lookers after rich ores, to make a fortune at once. The most common and easily obtained ores here are called "cascajos." They do not require roasting, as do the ores at Párac; but otherwise the silver is got out in the same manner as I have described it to be at that place. Instead, however, of the ground ore being placed in small piles, and, after being mixed with salt and mercury, trodden with the feet, and worked with hoes as it is at Párac, a large quantity is placed in a circular enclosure, with a stone floor and mud wall, and it is trodden with horses (as we used in old times to "tread wheat" in Virginia) until the amalgamation is completed. The general yield of the cascajos is six marks to the caxon. Their cost, according to the hardness of the rock in which they are enclosed, or their distance from the surface, is from six to sixteen dollars. Here is a calculation to show that, even at their highest price, of sixteen dollars, (being assured by the guia that the caxon will yield six marks,) their working, or benificiation, as it is called here, will pay. The complete amalgamation in the "circo," or circle, requires from forty to fifty days.
| Dr. | Circo of six caxones, a $16 caxon | $96 00 |
| 150 mule loads, (transportation to the hacienda,) a 25 cents | 37 50 | |
| Grinding, a $10 | 60 00 | |
| Magistral, (calcined iron pyrites,) 1 arroba | 1 00 | |
| 40 arrobas of salt, a 50 cents | 20 00 | |
| 5 tramplings by horses, a $5 | 25 00 | |
| Working and washing the amalgam | 11 50 | |
| Loss of 35 lbs. quicksilver, a $1 | 35 00 | |
| 286 00 | ||
| Cr. | 6 caxones, at 6 marks caxon, 36 marks. (Mark is worth in Cerro Pasco $8 50) | 306 00 |
I had this statement from Mr. Jump. I did not examine it at the time, but I observed afterwards that there is no charge for driving off the mercury of the amalgam, and leaving the pure silver, which is worth eight dollars and fifty cents the mark. This would amount to six dollars more, leaving the profit to the purchaser, for the two months that he has been engaged in getting his silver, but fourteen dollars. This, of course, is but a poor business; for, though any quantity of the ore maybe purchased, there are not haciendas enough to grind, or circos to amalgamate, a sufficient quantity to make the speculation good; and thus many millions of this ore are left unworked. The ore, however, rarely costs sixteen dollars, and will frequently give seven or eight marks to the caxon.
Statement showing the cost of a mark of silver placed on board ship for exportation:
| Cost of a mark of piña in the Cerro | $8 50 |
| Impost for steam machines for pumping water from the mines. (This has been 12½ cents, and soon will be 50 cents) | 25 |
| Socabon (or great drain) duty | 12½ |
| Public works | 6¼ |
| Government or export duty | 50 |
| Mineral tribunal duty | 12½ |
| Loss in running the piña into bars | 12½ |
| Carriage to Lima, and other petty expenses | 6¼ |
| Profit of the purchaser in the Cerro | 37½ |
| 10 12½ |
Twelve dwts. is the standard of pure silver in the mint at Lima. All the bars that go from this place are marked 11.22. They are assayed in Lima. If they come up to that standard they are worth $8.6746 the mark. For every grain under this 11.22 there is a deduction in the price of .0303 of a dollar.
To-day there was a meeting of the gremio, to take into consideration a question that had arisen whether the contractors for putting up the steam machinery for draining the mines had fulfilled their part of the contract. A short history of the draining of these mines may not be uninteresting, and will at all events put persons on their guard how they make contracts with miners.
The mines of Cerro Pasco were discovered in 1630, by an Indian making a fire on some stones and observing melted silver. They were worked, with little or no drainage, and with great success, up to the year 1780, when the socabon (or drain) of San Judas was commenced. This is a great ditch of five and a half feet in breadth and six feet ten inches in height, which drains the mines into the lake of San Judas. Its length is about thirty-five hundred feet, and it cost one hundred thousand dollars. It was finished in 1800. This would drain, by percolation, all the mines above it. For those below it, it was necessary to pump the water up by hand. This was found so inefficient a means, (the socabon also not being sufficiently large,) that in 1806 the gremio commenced the construction of the socabon of Quiulacocha, eighty-eight feet below that of San Judas, six feet ten inches broad, and eight feet three inches high. The work is continued upon it to this day. The part that I saw is arched, well walled with solid masonry, and the water rushes through it like a small river. Many lumbreras, or light holes, are sunk down upon it in various directions to give light and air, and to carry into the socabon the drainage of the neighboring mines.
In 1816, the gremio contracted with two Spaniards, Abadia and Arismendi, for the drainage of the mines by steam machinery. These persons put up three steam machines for working pumps, and the results were very happy, the ores being found much richer the farther down the mines reached. The war of independence broke them up; their miners being taken away for soldiers, and their machines used up for horse-shoes.