Humboldt’s Account of the Gold and Platina District of Russia.

The following account is part of a letter from M. Humboldt to M. Arago.—“We spent a month in visiting the gold mines of Borisovsk, the malachite mines of Goumeselvski, and of Tagilsk, and the washings of gold and platinum.

We were astonished at the pepitas, [water-worn masses] of gold, from 2 to 3lbs and even from 18 to 20lbs. found a few inches below the turf, where they had lain unknown for ages.

The position and probable origin of these alluvia, mixed generally with fragments of greenstone, chlorite slate, and serpentine, was one of the principal objects of this journey.

The gold annually procured from the washings amounts to 6000 kil.

The discoveries beyond 59° and 60° latitude become very important.

We possess the teeth of fossil elephants enveloped in these alluvia of auriferous sand.

Their formation, consequent on local irruptions and on levelling, is perhaps, even posterior to the destruction of the large animals.

The amber and lignites, which we discovered on the eastern side of the Ural, are decidedly more ancient.

With the auriferous sand are found grains of cinnabar, native copper, ceylanites, garnets, little white zicrons as brilliant as diamonds, anatase, anvite, &c. It is very remarkable, that in the middle and northern parts of the Ural, the platinum is found only on the western European side.

The rich gold washings of the Demidov family, at Nijnei-tagilsk, are on the Asiatic side, on the two acclivities of Bartiraya, where the alluvium of Vilkni alone has already produced more than 2800lbs. of gold.

The platinum is found about a league to the east of the separation of waters which must not be confounded with the axis of the high summits,) on the European side, near the course of the Oulka, at Sukoi Visnin, and at Martian. M. Schvetsov, who had the good fortune to study under Berthier, and whose learning and activity have been most useful during our travels in the Ural, discovered chromate of iron, containing grains of platinum, which an able chemist at Catherineburgh M. Helm, has analyzed.

The washings of Platinum at Nijnei-Tagilsk are so rich, that 100 puds (about 400lbs. Russian) of sand afford 30 sometimes 40 solotniks of platinum, whilst the rich alluvia of gold at Vilkni, and other gold washings on the Asiatic side, do not give more than 1½ to 2 solotniks in 100 puds of sand.

In South America a very low chain of the Cordilleras, that of Cali, also separates the auriferous and non-platiniferous sands of the eastern declivity Popayan from the sands of the isthmus of the Raspadura of Choco, which are very rich in platinum as well as gold.