Here the diamonds found in the district are deposited monthly, as they are received from the different works. They are carefully weighed, and some selected and kept separate. The average quantity obtained may be estimated at from 20,000 to 25,000 carats annually, which are sent under a military escort to Rio, and there lodged in the treasury.
The diamonds are tied up in black silk bags, and deposited in elegant inner cabinets, the whole of which are locked up in strong chests bound with iron.
They then showed me the gold, which was in large bars, weighing from five to ten pounds each, the whole of which I estimated at full 150lbs. weight. It was found in the district of Cerro do Frio, and was reserved to pay part of the expenses attending the establishment.
An excursion was some days afterwards proposed to another diamond work, called Rio Pardo, distant about twenty miles in a north-west direction. After proceeding a third of the way, over a country covered with a poor wiry sort of grass, we passed several fine falls of water, and crossed a ridge of mountains. The land as we advanced appeared much better, though still very naked, having only a few poor crooked small trees, that rather increased than took from its desolate appearance.
We passed through Chapada, a little dirty village, once famous for its washings, as were all the streams and ravines in the vicinity, and proceeded over some good clay-land, and a considerable tract of peat-moss, well watered by streams which burst in all directions from the hills. The country was open, and had a most romantic appearance, caused by a quantity of low rocks of soft pudding-stone, laminated, which lay on the surface in the most irregular forms. These lands were well calculated for pasturage, particularly in the season of abundance, but I was told that the cattle put to graze upon them were frequently stolen by the negroes[48], and that there were many noxious plants in the herbage which proved fatal to the beasts that ate them.
We arrived at the houses of the establishment about eleven in the forenoon, and walked four miles farther to the diamond works, on which a full troop of negroes was then employed. Rio Pardo is a dirty paltry-looking rivulet, which runs into the Rio Velho: in some parts it is confined by shelving rocks of quartz, through which it runs rapidly; in others it takes a serpentine course, and forms eddies, which are called caldrones, on account of their resemblance to the cavity of a boiler. The bed of the river, though confined, has a stratum of cascalho of variable thickness, which, after the current has been diverted, is dug up, and washed in the same way as at Jiquitinhonha. The caldrones, or holes, formerly eddies, but now partly filled with cascalho, so as to be no more than three or four feet deep, are frequently found to contain many diamonds; one of them, which was cleared by four men in as many days, produced one hundred and eighty carats.
Rio Pardo, though paltry and insignificant in its appearance, has produced as large a quantity of the most precious gems as any river in the district. The rough blueish-green-colored diamonds, formerly so much esteemed by the Hollanders, continue to be found here, and the stones of this rivulet are to this day reputed the most valuable in Brazil. The accompanying substances are somewhat different from those of the washings at Mandanga; here is no bean-like iron ore, but a considerable quantity of flinty-slate, like Lydian-stone, in various shapes and sizes, and very small black oxide of iron; the earthy matter is also much finer than at the above place. I was informed that there remained as much unworked ground as would occupy a hundred negroes full twenty years.
Rio Pardo runs about a league to the westward of Capella Velha, which is a chapel on a mountain, washed at its base by a stream, called Corgo de Capella Velha, which some years ago was worked, and produced diamonds of great size and superior brilliancy. The rivulets to the eastward of this ridge of mountains run into the Jiquitinhonha; those to the westward have their course into the Rio Velho, which flows into the Rio de San Francisco. The height of the mountains I had no means of ascertaining, but they are considered as undoubtedly the highest in Brazil. The air in this elevated region is pure and rather keen; the thermometer in the mornings and evenings stood at 62, and at mid-day about 74. In all the parts which I visited, the land appeared favorable for the growth of almost every species of produce, and, if properly inclosed and cultivated, might in no long time become the granary of the district.
On our return to Tejuco I was shown several dwarfish trees, of the height and size of a common crab-tree, with extremely crooked branches; and was informed that they were a species of the quercus suber. I cut from them some pieces of bark about an inch in thickness, which were elastic, and actually proved to be cork. It seemed to me a question of considerable interest, whether these trees, if regularly planted and attended to, might not produce cork of as good a quality as that which we obtain from the Mediterranean.