- 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 ...
Late Jurassic-Early Cretaceous diastrophism in Western North America.
Industry:Mining
Lathlike, rodlike, or acicular crystals in which the slow polarized light ray lies across the long direction of the crystal. Compare: positive elongation
Industry:Mining
Lava poor in silica, generally less than 52% total SiO<sub>2</sub>; typically dark and heavy, as basalt.
Industry:Mining
Law that governs the distance-dependence of physical effects, such as intensity of light, magnetism, and gravitational force. The effect at a point due to an emitting source varies as the square of the distance between them.
Industry:Mining
Layers or bands that are petrographic entities, recognizable visually as bands or layers of coal that have distinctive physical appearance and characteristic microstructural features from coal to coal.
Industry:Mining
Lead (Pb) having four isotopes (mass numbers 204, 206, 207, and 208) in the proportions generally obtained by analyzing lead from rocks and lead minerals that are associated with little or no radioactive material; commonly considered to be the lead present at the time of the Earth's formation, as distinguished from lead produced later by radioactive decay.
Industry:Mining
Lead derived from salvage of wornout end-product items, such as battery plates, cable covering, pipe and sheet, which are collected, remelted, and refined in secondary smelters to produce refined lead or various lead-base alloys.
Industry:Mining
Lead free from any silver, and often finely granulated; used in testing or cupelling, assaying, etc.
Industry:Mining
