- 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 ...
Applied in the gem stone trade to yellow transparent quartzes resembling Brazilian topaz in color; used for ornamental purposes.
Industry:Mining
Applied in the grading of quartz crystals to feathery or fernlike types of foreign inclusions, which look soft (no implication of physical hardness).
Industry:Mining
Applied in the grading of quartz crystals to needlelike imperfections, often definitely oriented, which show up with a bluish-white color under the carbon arc. The color is due to the selective scattering of blue light by the minute imperfections.
Industry:Mining
Applied in the trade to a natural mass of quartz bounded by one or more of the original crystal faces.
Industry:Mining
Applied to a belt of country in which the rock is cracked in all directions, resulting in a network of small veins.
Industry:Mining
Applied to a boulder, block, or larger rock body unrelated to the rocks with which it is now associated, which has been moved from its place of origin by one of several processes. Exotic masses of tectonic origin are also allochthonous; those of glacial or ice-rafted origin are generally called erratics.
Industry:Mining
Applied to a dormant or decadent stage of volcanic activity characterized by the emission at the surface of gases and vapors of volatile substances.
Industry:Mining
Applied to a method of blasting on a face not exceeding 30 ft or 35 ft (9.1 m or 10.7 m) in height. It involves leaving at the quarry face a mass of shattered rock several feet in 329 thickness that serves as a buffer, preventing the rock from being thrown far from its source, and also rendering the shot more effective.
Industry:Mining
Applied to a method of blasting on a face not exceeding 30 ft or 35 ft (9.1 m or 10.7 m) in height. It involves leaving at the quarry face a mass of shattered rock several feet in 329 thickness that serves as a buffer, preventing the rock from being thrown far from its source, and also rendering the shot more effective.
Industry:Mining
