- 行业: Mining
- Number of terms: 33118
- Number of blossaries: 0
- Company Profile:
The U.S. Bureau of Mines (USBM) was the primary United States Government agency conducting scientific research and disseminating information on the extraction, processing, use, and conservation of mineral resources.
Founded on May 16, 1910, through the Organic Act (Public Law 179), USBM's missions ...
A deflagrating or low-explosive granular compound of sulfur, charcoal, and an alkali nitrate, usually potassium or sodium nitrate.
Industry:Mining
A degree of diaphaneity between translucent and opaque. Passes light through edges of cabochons but very little through thicker parts.
Industry:Mining
A degree-day unit based on a (usually) 45 degrees F or 55 degrees F (7.2 degrees C or 12.9 degrees C) mean daily temperature so as to be applicable to industrial buildings maintained at relatively low temperatures.
Industry:Mining
A delay pattern that causes the true burden, at the time of detonation, to be formed at an oblique angle from the original free face.
Industry:Mining
A delicate vertical-angle adjustment for the vernier on the alidade, graduated in hundredths of a revolution. Compare: tangent screw
Industry:Mining
A dense medium washer consisting of a static bath. The floats, or clean coal, are removed by means of paddles or chains suspended from bars connected to rotating spokes. The sinks, or shale, are extracted by a scraper device. The bath can be fed directly from the raw coal screens. The separator has been developed for the treatment of large coal.
Industry:Mining
A dense siliceous rock having the texture, dull luster, hardness, conchoidal fracture, and general appearance of unglazed porcelain; it is less hard, dense, and vitreous than chert. The term has been used for: an impure chert, in part argillaceous; an indurated or baked clay or shale often found in the roof or floor of a burned-out coal seam; and a finegrained, acidic tuff compacted by secondary silica. Etymol: Italian porcellana, porcelain. Also spelled: porcelanite; porcelainite.
Industry:Mining
A dense spherical calcareous concretion, usually white or light-colored, consisting of occasional layers of conchiolin and predominant nacrous layers of aragonite (or rarely calcite); deposited concentrically about a foreign particle within or beneath the mantle of various marine and freshwater mollusks; occurs either free from or attached to the shell.
Industry:Mining
A dense-media coal cleaning process in which the separating medium consists of minus 200-mesh magnetite (sp gr, 5.2) in water in the desired proportions (4.4 parts of water to 1 part of magnetite provides an effective specific gravity of about 1.9). This process has the advantage that the medium requires little agitation to keep it in suspension and is easily removed from the clean coal and refuse.
Industry:Mining
