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Show 584 WESTERN WILDS. crystallization of minerals. One forms a cube, another a hexagon, another a tetrahedron, and still another a dodecahedron ; some com-bine with faces at certain angles, and lines of cleavage parallel there-with ; others at just half that angle, and still others in multiform fig-ures for which geometry has no name, but all symmetrical beyond the power of art to surpass. And no matter how broken, each crystal fol-lows the law of its cleavage; the cube breaks into cubes, the hexagon into hexagons, etc. Sulphuret is the generalname of all silver ores in combination with sulphur. They are generally rich, mostly in hard rock, and always more or less rebellious. Nearly all the rich ores of eastern Colorado are of this class. The combinations are almost endless, and the pres-ence of zinc, iron, or copper pyrites, antimony, arsenic, etc., presents a perplexing series of problems to the mill men. Sulphurets yield from $ 200 to $ 10,000 per ton, one mine sometimes yielding several different grades. Here and there on the face of an ore- seam are some-times found little accretions of pure silver, Avhich miners speak of as " the fat of the vein." It is supposed that there was more silver than the other materials could hold in chemical union, so it overflowed in these nibs, which hang on the face of the seam like leaf- lard. Ac-cording to their purity, or the minerals mixed with them, such nibs are known as wire silver, horn silver, ruby silver, silver glance, azurite or tetrahedrite. A change of less than one per cent, in the accompa-nying chemical will often change entirely the color of such ore. Azurite is a combination of silver with blue carbonate of copper, and yields anywhere from $ 500 to $ 10,000 per ton. Tetrahedrite is so named from its crystallizing in tetrahedrons. Sulphurets of other metals are constantly met with, and greatly increase the difficulty of reduction. " Black- jack," or zinc- blend, a sulphuret of zinc and cop-per, is a very troublesome combination. Chunks of it have been found assaying $ 500 per ton, but no man is anxious to find it in his mine for all that. It looks like a lump of black wax turned to vitre-ous stone, and is spoken of as " horribly rebellious." I have seen a lump of stuff from a sulphuret mine, no larger than my fist, which was shown by assay to contain twenty different minerals. Iron pyrites is a sulphuret of iron, protean in appearance, jocularly known as fool's gold. Most of the reported discoveries in the eastern states are due to this cheating mineral. In conclusion it may be said that from the differences herein de-scribed some important political consequences follow. First, that placer mines are almost a curse to a country, while lodes requiring |