This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1865 edition. Excerpt: ...compound. We have already shown how metals are produced and liberated from rocks by decomposition, and shall now explain the formation of sulphuretted ores in the fissures of rocks from mere joints to the magnitude of great lodes. Sulphurets were formerly considered as scarcely explicable in the wet way, ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1865 edition. Excerpt: ...compound. We have already shown how metals are produced and liberated from rocks by decomposition, and shall now explain the formation of sulphuretted ores in the fissures of rocks from mere joints to the magnitude of great lodes. Sulphurets were formerly considered as scarcely explicable in the wet way, sulphur being supposed insoluble in water; but we find innumerable springs holding sulphur in solution, such as sulphuretted hydrogen, as already explained. All metals are held in solution in a weak alkaline mixture and in different compounds. Carbonate of lead is soluble in alkali and lime, and precipitable therefrom by sulphuretted hydrogen. It has a greater affinity for lime than for any other earths; hence limestone formations contain lead in preference to other metals; marshes are also usually more productive of masses of lead ore than the higher and drier parts of the roek. The carbonate of lime not only accompanies galena or sulphuret of lead in the limestone rocks, but also very frequently in the clay-slate and porphyritic formations, as a matrix of the ore. The most pure metals, when sufficiently divided, are soluble in water; and it has been shown that silver, as well as mercury, lead and copper, &c., are taken up by water and deposited on the surface of rifts, as in the Christiania mines in Norway, in Peru, and in a number of other mining districts. When, therefore, water impregnated with sulphur meets with the same element charged with metals, permeating the joints and pores of the rocks, precipitation takes place and forms a compound in accordance with the laws of affinity; but this formation of sulphurets is again subject to be dissolved and dispersed by an alkaline reaction, as proved in many instances. In Peru and Chili pieces...
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Add this copy of Geology and Terrestrial Magnetism to cart. $58.91, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2011 by Nabu Press.
