Treatise on Mineralogy: Or, The Natural History of the Mineral Kingdom, Volum 2

A. Constable and Company, 1825

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Side 15 - Manual of Mineralogy : containing an account of simple Minerals ; and also a description and arrangement of mountain rocks.
Side 264 - A third variety of this species, employed in jewelry, is the avanturine feldspar, which comes from the island of Cedlovatoi, near Archangel, and which is of a honey-yellow color, and every where penetrated by little golden spangles. 4. The pure varieties of feldspar are used in the composition of the paste of porcelain ; also for the enamel with which it is covered ; and the decomposed variety, or porcelain earth itself, is the most important material in that department of manufactures. (See...
Side 183 - Water 14.50 Alone, it becomes yellow before the blowpipe, and loses its transparency. Upon charcoal, it intumesces a little, and melts into a black globule. It occurs in veins of copper, silver, tin and iron. Beautiful varieties have been found in the Gunnis lake mine, in Cornwall. It also occurs in the Saxon and Bohemian mining districts. It is likewise met with at...
Side 336 - ... 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 439 - Scheelium-baryte. In veins it occurs along with nearly the same minerals, but likewise with many others, of the orders Glance, Pyrites, Blende, Baryte, Haloide, Metal, &c. Hexahedral Gold is often found in the sand of rivers, in valleys and plains into which it has been carried from its original repositories, in the shape of larger or smaller, generally flat pebbles, often mixed with rhombohedral Quartz. From the generally high gold-yellow colour of these varieties, it seems probable that they are...
Side 451 - Its chemical composition is, iron 33.5, arsenic 46.5, and sulphur 20. Before the blow-pipe, upon charcoal, it emits copious arsenical fumes, and melts into a globule, which is nearly pure sulphuret of iron. It is soluble in nitric acid, with the exception of a whitish residue. It sometimes contains a small proportion of silver ; when it is denominated argentiferous arsenical pyrUes.
Side 193 - 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 1 - 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 413 - 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 - The different kinds of marble have been distinguished and denominated, and are prized, according to pureness, colour, delineation', translucency, size of the component individuals, and of the blocks which may be obtained free from fissures and blemishes ; also according to the degree of polish they receive, &c. The more common or coarse varieties are used for the common purposes of building, also for paving streets. A peculiar variety of very fine grained compact limestone is used for plates in lithography....

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