Treatise on mineralogy, or The natural history of the mineral kingdom, tr. with additions by W. Haidinger, Volum 2

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Side 335 - ... formation. Lately, however, some very fine specimens of this substance have bee"n discovered in the Faroe islands; and most beautiful ones, sometimes quite transparent, are obtained near Gracias a Dios, in the province of Honduras, in America.
Side 51 - ... off. It effloresces from several rocks, both in their original repository and in artificial walls, and then it is a product of their decomposition. It forms the principal ingredient of certain mineral waters. it occurs at Freiberg and its vicinity, efflorescing upon gneiss, also at the quicksilver mines of Idria, in Carniola, and various other places in Europe. Its most remarkable depositories, however, are the limestone caves of Kentucky, whose floors are often covered with it, in delicate crystals,...
Side 194 - SCHEEI.E. 0-00. VAUO. 0-00. SAUss. In a high degree of heat it is combustible, and leaves a residue of oxide of iron. It is infusible alone, and with additions. 3. The varieties of this species are found in beds, or form beds by themselves, in slaty and ancient trap-rocks. They seem often to replace the different species of Talc-mica in mixed rocks, particularly in gneiss, if containing a great proportion of Feld-spar. In the beds of rhombohedral Lime-haloide, the rhombohedral Graphitemica occurs...
Side 2 - Physiography, the last head of scientific mineralogy, consists of the assemblage of the general descriptions, and is intended to produce a distinct image of minerals. We cannot, by its assistance, find the place of a given mineral in the system, or, in other words, recognise it ; for it is independent of that connexion, among minerals, upon which the system is founded.
Side 434 - ... 10.47. Native silver has been distinguished into common and auriferous native silver: the former consists of silver alloyed with a small proportion of antimony, arsenic, iron, &c.; the latter frequently contains fifty per cent, of gold. Native silver occurs principally in veins, traversing gneiss, clay-slate, and other primitive and transition rocks.. There are but few countries in which it is found in any considerable quantity. Among these are the mining districts of Saxony and Bohemia, also...
Side 119 - Carbonic acid. It is soluble with effervescence in the muriatic and nitric acids; and paper, dipped into this solution and afterwards dried, will burn with a red flame. It melts before the blowpipe at a temperature not very elevated, but only on the thinnest edges. It intumesces, and spreads a brilliant light ; the flame at the same time assumes a reddish hue. It is dissolved by borax with a violent effervescence into a clear globule.
Side 412 - It melts, with borax, into a green or yellow glass, and is soluble in heated nitro-muriatic acid. The division introduced among the varieties of the present species, is somewhat similar to that which has been given to red iron ore. Crystallized hydrous oxide of iron embraces the small black crystals, which sometimes occur in fibrous and radiating bundles.
Side 93 - Lime-ha'oide is a species widely diffused in nature, and several of its compound varieties have a considerable share in the constitution of mountains in many countries. So they appear in Switzerland, Italy, Carniola, Carinthia, Salzburg, Stiria, Austria, Bavaria, Suabia, &c. The earthy varieties of chalk occur in the low lands, or on the sea-shores of England, France, Denmark, Poland, &c. Beds of granular limestone occur in gneiss, mica-slate, clay-slate, &c. ; beds of compact limestone likewise...
Side 329 - Quartz frequently fills up the space of petrified bodies, as, for instance, echinites in chalk, and petrified wood in sandstone and in alluvial deposits. 5. The numerous varieties of the present species are spread all over the globe, but some of the most distinguished varieties are found only in a few localities. The finest and largest Rock-crystals of high degrees of transparency are found in the alps of Salzburg, the Tyrol, Switzerland, Dauphiny, Piedmont, and Savoy, also in the isle of Madagascar,...
Side 94 - Several varieties of the present species are usefully employed for various purposes, partly depending upon their mechanical, partly upon their chemical composition. Those used in sculpture, and in ornamental architecture, are called Marble, several varieties of which are celebrated, and their localities well known.

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