SERPENTINE STONE, a genus of magnesian earths, of which there are different species: 1. The fibrous, composed of fibrous and coherent particles. This resembles the asbestos so much that it might be confounded with it, were not the fibres of the serpentine so closely coherent, that they cannot be distinguished when the stone is cut or polished. The fibres themselves are large, and seem to be twisted. There are two varieties, a dark green and a light one; the former from Germany, the latter from Sweden. 2. The zo-blitz serpentine, found near that place, of many different colours, as black, deep green, light green, red, bluish-grey, and white; but the green colour is most predominant. 3. Porcelain earth mixed with iron. It is met with either diffusible in water or indurated. The former is found of a red colour from China and Montmartre. The water-chinkens, imported from some places in Germany, seem to be made of this kind of earth. There are two varieties of the indurated kind, viz. the martial soap-earth, of a red colour, from Jüberg and other places in Norway, or black from some parts of Sweden. 4. The telgton of the Swedes, the same with the lapis ollaris. It is found in various pieces of Norway, as light grey, dark grey, whitish yellow, and dark green. It is employed with great advantage for building fire-places, furnaces, &c. the extremities of the strata being turned towards the fire when it is flaty.
M. Magellan observes, that there is a great variety of colour as well as composition in this kind of stones; it being found either white, green, brown, yellow, light-blue, black, spotted, or streaked with veins of different colours. Its texture is either indistinct, obliquely laminar, or fibrous. The specific gravity is from 2400 to 265; and it is harder than soap-rock or steatites; though not hard enough to strike fire with steel; being less smooth to the touch than steatites, but susceptible of a good polish, looking like marble; and is often met with in thin semitransparent plates. It melts in a strong heat without addition, and corrodes the crucibles, but hardens in a lower degree of heat. It is slowly and partially soluble in acids, but does not effervesce with them. According to Bayon's analysis, 100 parts of it contain about 41 o' silex, or rather mica; 33 o' magnesia; 20 o' argillaceous earth; 12 o' water, and about 3 o' iron. That brought from Corsica contains a greater proportion of argil, and a smaller one of silex. The serpentine commonly so called, according to Fabroni, is a true lapis ollaris; but has its name from being variegated with green, yellowish, and brown spots, like the skin of some serpents; great quantities of it are found in Italy and Switzerland, where it is frequently worked into dishes and other vessels.