- 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 ...
These machines have powerful electromagnets in a wedge section. The material is treated on rolls on which magnetism is induced; they consist of alternate disks of soft iron and some nonmagnetic material. The ore is fed over the first roll, which removes the most magnetic material, and the tailings go on to the second, which is weaker, where a second separation is made.
Industry:Mining
These may be either longitudinal or transverse and consist of rails of various sizes, placed in sets usually upside down, either longitudinally in the sluice box, or transversally across the box. They wear well, are rigid, and give some security against theft of gold from the sluice boxes.
Industry:Mining
These occur in the mineral deposit itself or in adjacent or nearby formations. Their origin may be in a particular formation in which they were laid down or formed subsequently by chemical action, or they may occasionally migrate into other formations, frequently because of release of pressure with mining. Water flow and rock porosity and fissures also allow gas migration. The principal strata gases are methane, carbon dioxide, nitrogen, sulfur dioxide, hydrogen sulfide, and radon.
Industry:Mining
These usually consist of a number of filtering leaves that are simply rectangular frames carrying filter cloth on the outer surface. A number of these leaves are mounted in a suitable tank, and the clear liquid passes through the filter cloth and out through pipes leading from the interior of each filter leaf. The solid material forms a cake on the outside of the leaf.
Industry:Mining
These words refer to the time of the location and commencement of the tunnel and not to the respective times of the discoveries of the various veins in the tunnel.
Industry:Mining
Thick sulfur-bearing deposits may be worked by a network of tunnels and general caving. The bed is extracted in a series of thick slices, horizontal if the dip is great, or parallel to the dip if it is moderate.
Industry:Mining
Thickness of consolidated rock above the roof of an opening (equivalent to cover, minus depth of weathering or of other soil). Compare: cover
Industry:Mining
Thin layer or parting of shale between harder strata, primarily a driller's term. Compare: shell
Industry:Mining
