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.