On the 1st of January, 1772, the diamond district came under the immediate management of the government. But diamonds alone do not constitute the riches and celebrity of this district; other precious stones concur in rendering it important, such as sapphires, emeralds, aqua-marinas, chrysolites, topazes, &c. All these stones are produced in the serras, from whence they descend to the rivers, with the waters of the copious thunder showers. This district also possesses mines of all the metals, the extraction of which is rigorously prohibited on account of the diamonds. Around the diamond district there are various military detachments, to prevent the plunder of those stones, or of gold; and also to exact the duties paid upon entrance. Amongst those stations may be enumerated, first, Milho Verde; and, next in rotation, Pirahuna, Gouvea, Rio Pardo, Chapada, Arraial, Hinhahy, Rio Manço. The diamond demarcation, afar off exhibits a black perspective, swelling into a thousand rugged and uneven serras; on one hand are elevated mountains of one single stone, cut by nature into precipices that raise their heads to the clouds; on the other, are extended serras, composed of detached rocks and stones, accumulated on each other in chaotic piles, covered with a grey moss, and sparingly dressed in creeping brushwood. A thousand pure and crystalline rills warble across its rude tracts formed by the miner, and roll into his _gamella_[25] their rich offerings. The waters of some are dashed over the sides of mountains, others descend divided between broken rocks to the base of the serras, from whence, accumulating, they flow in serpentine courses in search of larger rivers, running sometimes tamely and tranquilly between spacious banks; at others, precipitated amongst approximating and steep serras, with loud and interesting murmurs. For a time they often disappear altogether from the sight, are again visible, flowing on in foaming fury. The crystallizations of diamonds are obtained near the surface of the earth. Their form is triangular, round, pointed on one side, with the face always smooth; this proves that the crystallization is dispersed and solitary.