The Paulists and inhabitants of the ancient captaincy of St. Vincent were the first who discovered these mines, and peopled, in great part, the whole of this rich province, as well as those of _Matto-Grosso_, _Cuiahe_, _Goyares_, and _Rio Grande de San Pedro_. Anthonio Soary, a Paulist, who gave his name to one of these mountains, was the first who discovered and visited the _Sero-Dosrio_. Gold only was sought for, but at last diamonds were discovered in the _Riacho Fundo_, whence they were first obtained, and afterwards in the _Rio de Peire_; a great number were likewise obtained from the _Giguitignogna_, a very rich stream; and, lastly, in the end of 1780, and beginning of 1781, a gang of nearly three thousand interlopers, called _Grimpeiros_, discovered diamonds, and obtained an immense quantity from the _Terra de Santo Antonio_; but they were forced to abandon this spot to the royal farm, who took possession of it. Then it was that the suspicion was confirmed, that the mountains are the true _matrices_ of diamonds; but as the work in the beds of rivers and on their banks is less tedious, can be conducted on a larger scale, and affords larger diamonds, the farm abandoned the mountains, and formed great establishments in the river of _Toucanbirnen_, which flows through the valleys of this chain, and is near ninety leagues in length. It was found by examination and digging, that the whole surface of the ground, immediately beneath the vegetable stratum, contained more or less of diamonds, disseminated and attached to a matrix ferruginous and compact in various degrees, but never in veins, or in the division of geodes. _Figure of the Diamonds, and manner of exploring them._ The figure of the diamonds of Brazil varies. Some are octoedrical, formed by the union of two tetraedrical pyramids. This is the _Adamas octoëdrus turbinatus_ of Wallerius, or the octoedrical diamond of Romé de l'Isle. These are almost always found in the crust of the mountains; others are nearly round, whether by a peculiar crystallization or by rolling. They resemble those Oriental stones, which the Portugueze and natives of India call _reboludos_, which signifies rolled. Lastly, others are oblong, and appear to me to be the _Adamas hexaëdrus tabellatus_ of Wallerius. The two last are usually found in the beds of rivers and broken places in their banks.