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

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A. Constable and Company, 1825
 

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Side 394 - Vauquelin's analysis of another specimen gave as above, respectively, 55-5, 33, 6, and 2. It is infusible before the blowpipe ; but it acts upon the magnetic needle, after having been exposed to the reducing smoky flame. It is entirely soluble in borax, at a high blowpipe heat, and imparts to it a beautiful green color.
Side 449 - 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 419 - Radiated gray manganese ore comprises long acicular, or reed-like prisms, and such massive varieties as consist of columnar particles of composition, while the foliated one refers to short prisms and granular compositions. Compact gray manganese ore contains varieties composed of impalpable granular individuals, and earthy gray manganese ore, such as have lost their coherence, and appear in the state of an earthy powder. The composition of some varieties belonging to this species, has been found...
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 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 v - 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 293 - Before the blowpipe it loses its colour, but does not melt. It is slowly and difficultly dissolved in borax. With boracic acid and iron- wire it yields a globule of phosphuret of iron. 2. Prismatoidal Azure-spar occurs in masses, sometimes pretty considerable, also in large indistinct crystals imbedded in rhombohedral Quartz, and mixed with Mica. It has not been found in its original repositories, which seem to be beds. 3. It occurs in the valley of Freschnitz near Krieglach on the MUrz in Upper...
Side 411 - 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 419 - It is infusible before the blow-pipe, and colors glass of borax violet blue. It is insoluble in nitric acid. In heated sulphuric acid, it disengages oxygen ; and chlorine is evolved, if it is brought into contact with muriatic acid; also, before the blow-pipe, or alone in a strong heat, it gives out oxygen. The gray manganese ore frequently accompanies the haematitic iron ores ; and sometimes its earthy and compact varieties constitute beds by themselves.
Side 92 - Lime-haloide 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...

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