a. Liquefaction of a gel; deflocculation and dispersion of solids in a
pulp; conversion of a substance to its colloidal state by subdivision.
Pryor, 3
b. A dispersion due to the addition of electrolytes or other chemical
substances. Brantly, 1
To bring into colloidal solution; to convert into a solution.
Syn:deflocculate
Said of igneous rocks in which the molecular proportion of alumina is less
than that of soda and potash combined.
Said of igneous rocks in which the molecular proportion of alumina exceeds
that of soda, potash, and lime combined.
The proportion of a coal seam that is removed from a mine. The remainder
may represent coal in pillars or coal that is too thin or inferior to mine
or is lost in mining. Shallow coal mines working under townships,
reservoirs, etc., may extract only about 50% of the entire seam, the
remainder being left as pillars to protect the surface. Under favorable
conditions, longwall conveyor mining may extract from 80% to 95% of the
entire seam. With pillar methods of working, the extraction ranges from
50% to 90%, depending on local conditions. Nelson
N.S.W. In most cases, understood to be the percentage of the metallic
element present in the ore. New South Wales
The measured amount of subsidence expressed as a percentage of the
thickness of coal extracted. See also:full subsidence
The percentage of the total wall area of a mine that will actually be
covered by supports. Spalding
a. Any of various units of measure for stonework, (including 24-3/4 ft
3 (0.70 m3 ) representing a pile 1 rod (5.0 m) long by 1
ft (0.3 m) by 1-1/2 ft (0.46 m); or 16-1/2 ft3 (0.47 m3
); or 25 ft3 (0.71 m3 ). Webster 3rd
b. A measure of length equal to 5-1/2 yd or 16-1/2 ft (5.0 m); a rod, or
pole; also, a square rod (25.3 m2 ). Webster 2nd
Unconfined ground water separated from an underlying main body of ground
water by an unsaturated zone. AGI
The water table of a body of perched ground water.
See:vertical sand drain
a. In the leaching treatment of minerals, a process whereby a solvent
flows gently upward or downward through a bed of ore-bearing material
sufficiently coarse textured to permit this flow.
See also:sand leaching
b. Slow laminar movement of water through small openings within a porous
material. Also used as a syn. of infiltration. Flow in large openings such
as caves is not included. CF:infiltration
The selective removal of the metal values from a mineral by causing a
suitable solvent or leaching agent to seep into and through a mass or pile
of material containing the desired mineral.
The rate, expressed as either velocity or volume, at which water
percolates through a porous medium. AGI
A rock-drilling tool with chisellike cutting edges, which when driven by
impacts against a rock surface, drills a hole by a chipping action.
Long
See:detonator; primer.
a. Drill in which the drilling bit falls with force onto rock. Also, a
pneumatic drill in which a piston delivers hammer blows rapidly on the
drill shank. Syn:churn drill; cable-tool drill; percussion machine.
Pryor, 3
b. Sometimes limited to large blasthole drills of the percussion type.
Nichols, 1
Act of using a percussion drill. See also:percussion drill
A pattern of radiating lines produced on a section of a crystal by a blow
from a sharp point.
See:percussion drill