The Natural History of the Mineral Kingdom (Volume 1) (Paperback)

This historic book may have numerous typos, missing text or index. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. 1810. Not illustrated. Excerpt: ... CHAP. II. pF THE MINERAL SUBSTANCES WITH WHICH VEINS ARE FILLED. One of the greatest points of difficulty in describing wide veins, is to convey a proper idea of the various mineral substances, hard and soft, and of the various conditions of the ores found in such veins; for it would be a very easy matter to say that a vein is so many feet or yards wide: But the various phenomena of the inside of these veins, and of the soils or mineral matters they contain, is not easily described or conceived, without seeing them in their various appearances. I observed before, that the two sides of a mineral vein are called by miners the hanger and led. g?r. These sides are always of the rock or strata wihich compose the mountain or mining field, the vein being a crack or fissure in those strata. What are called dead veins, that is, those which do not bear ore at the surface, or produce any upon such trials as may be made in them, frequently contain between their sides, in different places, a vast variety of mineral stones and soft mineral soils. The most common and the most promising of the mineral stones, as concomitants of ore, are the spars and vein-stones of different species. What I call vein-stone, is a compound mineral concretion, of various colours, appearances, and degrees of hardness, and not unfrequently of various colours in the same mass. This compounded stony concretion is called by miners a rider, perhaps from its riding the vein, or separating it longitudinally into two or more divisions. This mineral stone is sometimes hard and heavy, sometimes compact and solid, but frequently cracked and cavernous, and rising in irregular and misshapen masses. A rider frequently contains a variety of different sub stances in the same mass, such as spar, quartz, fragments o...