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United States Bureau of Mines
Industry: 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 crystal of one species enclosing one of another species.
Industry:Mining
A crystal or mineral aggregate within which an earlier stage of crystallization or growth is outlined by dust, tiny inclusions, or bubbles; e.g., a trigonal scalenohedron of calcite coated with hematite and overgrown with a clear calcite rhombohedron in crystallographic continuity.
Industry:Mining
A crystal or mineral aggregate within which an earlier stage of crystallization or growth is outlined by dust, tiny inclusions, or bubbles; e.g., a trigonal scalenohedron of calcite coated with hematite and overgrown with a clear calcite rhombohedron in crystallographic continuity.
Industry:Mining
A crystal structure deviating from ideality by having two or more chemical species in one or more crystal sites. Compare: crystal defect; disorder.
Industry:Mining
A crystal structure resulting from large unit cells when an alloy inverts from disordered occupancy of lattice sites by "averaged" constituent atoms in small unit cells to individual atomic species occupying specific lattice sites and having long-range order; e.g., disordered Cu<sub>3</sub>Au has a primitive cubic unit cell with averaged "Cu-Au atoms" at each corner, while ordered Cu<sub>3</sub>Au has a face-centered cell with Au atoms its corners and Cu its face centers, the large face-centered unit cell containing eight of the small primitive unit cells. See: superlattice; long-range order.
Industry:Mining
A crystal surrounded by another crystal of a different mineral species. Adj. endomorphic, endomorphous.
Industry:Mining
A crystal that has grown during metamorphism without the development of its characteristic faces. Compare: idioblast.
Industry:Mining
A crystal twin consisting of four individuals; characteristic twinning exhibited by some varieties of authigenic microcline. Compare: trilling; fiveling; eightling.
Industry:Mining
A crystal whose faces have developed unequally, some being larger than others. Some distorted crystal forms are drawn out or shortened, but the angle between the faces remains the same.
Industry:Mining
A crystal with a conductive surface film of gold, silver, aluminum, or other metal produced by cathode sputtering, evaporation, or chemical methods. The films, to which lead wires may be soldered, take the place of the conventional clamped metal electrodes.
Industry:Mining