- 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 classification of coals based primarily upon the carbon and hydrogen content calculated to a pure-coal basis, according to the Parr formula.
Industry:Mining
A classification of igneous rocks based on crystallinity, degree of saturation with silica, degree of saturation with alumina, and color index. This system was developed in 1927 by S.J. Shand.
Industry:Mining
A classification of rocks made in the field. It is based on features distinguishable in hand specimens by using a hand lens, a knife, an acid bottle, etc. The classification may be refined or modified by subsequent examination with a microscope or other techniques that are generally used in a laboratory.
Industry:Mining
A classification system based on the proximate analysis and calorific value of ash-free, dry coal. The heating value of raw coal is obtained, and from these data a table is drawn up, at one end of which are the celluloses and woods of about 7,000 Btu/lb (16.3 MJ/kg). These data are then plotted against the percentage volatile matter in unit coal.
Industry:Mining
A classifier of the free-settling type in which the settled material is removed by dragging it up an inclined plane by means of a continuous belt of flat blades or paddles. It is continuous in its operation.
Industry:Mining
A classifier operating in such a manner that the pulp grains fall through a sorting column against an upward pulsating current of water. It has no screen.
Industry:Mining
A clastic sedimentary rock that is made up almost exclusively of quartz sand (with or without chert), and relatively free of or lacks a fine-grained matrix, derived by secondary 2202 silicification; a quartzite of sedimentary origin, or a pure quartz sandstone. The term generally signifies a sandstone with more than 90% to 95% quartz and detrital chert grains that are well-sorted, well-rounded, and cemented primarily with secondary silica (sometimes with carbonate) in optical and crystallographic continuity with the grains. The rock is characterized by stable but scarce heavy minerals (zircon, tourmaline, and magnetite), by lack of fossils, and by prominence of cross-beds and ripple marks. It commonly occurs as thin but extensive blanket deposits associated with widespread unconformities (e.g., an epicontinental deposit developed by an encroaching sea), and it represents intense chemical weathering of original minerals other than quartz, considerable transport and washing action before final accumulation (the sand may experience more than one cycle of sedimentation), and stable conditions of deposition (such as the peneplanation stage of diastrophism); e.g., St. Peter Sandstone (Middle Ordovician) of midwestern United States.
Industry:Mining
A clay consisting mainly of colloidal aluminum silicate from British Columbia, Canada.
Industry:Mining
A clay containing burls; specif. a diaspore-bearing clay in Missouri, usually averaging 45% to 65% alumina.
Industry:Mining
