- 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 bridge where a return airway passes over (overcast) or under (undercast) an intake airway. It is generally constructed with concrete blocks, structural steel, and/or sheet metal, and is made airtight to prevent intermixing of the two air currents. The mining law requires an air crossing to be so constructed as not to be liable to be damaged in the event 71 of an explosion.
Industry:Mining
A bridge where a return airway passes over (overcast) or under (undercast) an intake airway. It is generally constructed with concrete blocks, structural steel, and/or sheet metal, and is made airtight to prevent intermixing of the two air currents. The mining law requires an air crossing to be so constructed as not to be liable to be damaged in the event 71 of an explosion.
Industry:Mining
A brief explanatory list of the symbols, cartographic units, patterns (shading and color hues), and other cartographic conventions appearing on a map, chart, or diagram. On a geologic map, it shows the sequence of rock units, the oldest at the bottom and the 1775 youngest at the top. The legend formerly included a textual inscription of, and the title on, the map or chart.
Industry:Mining
A brief explanatory list of the symbols, cartographic units, patterns (shading and color hues), and other cartographic conventions appearing on a map, chart, or diagram. On a geologic map, it shows the sequence of rock units, the oldest at the bottom and the 1775 youngest at the top. The legend formerly included a textual inscription of, and the title on, the map or chart.
Industry:Mining
A bright coal (composed of anthraxylon and attritus in which the translucent cell-wall degradation matter or translucent humic matter predominates) in which the ratio of anthraxylon to attritus is from 3:1 to 1:1. Compare: attrital coal.
Industry:Mining
A bright coal (composed of anthraxylon and of attritus in which the translucent cell-wall degradation matter or translucent humic matter predominates) in which the ratio of anthraxylon to attritus is less than 1:3.
Industry:Mining
A bright, apple- or blue-green variety of microcline; may be carved for art objects.
Industry:Mining
A bright, apple- or blue-green variety of microcline; may be carved for art objects.
Industry:Mining
A bright, silvery, lustrous, metallic element of the rare-earth group. Symbol, Sm. It is found along with other members of the rare-earth elements in many minerals, including 2747 monazite and bastnasite, which are commercial sources. Used for carbon-arc lighting for the motion picture industry, for permanent magnets, and in optical masers and lasers.
Industry:Mining
A brilliant split apart at the base of its pyramidal forms, so as to make two gems.
Industry:Mining
