Coarse sizes of rock salt, usually No. 2 or No. 1. Kaufmann
a. The crest or culmination of a structure, such as a dome or an
anticline. CF:low
b. Name for the coal of a thick seam. Fay
c. A geophysical anomaly with values greater than normal; e.g., a gravity
maximum or a geothermal maximum. AGI
Alumina-silica refractories containing 45% or more alumina.
Harbison-Walker
A fault with a dip greater than 45 degrees . CF:low-angle fault
Billings
Carbon steel that contains more than 0.5% carbon. Hammond
Metal of high purity, having an electrical conductivity not much below
that of the international standard, which is a resistance of 0.15328 Omega
for a wire 1 m long and weighing 1 g. CTD
Scot. An upper landing in a shaft. Fay
A method of fighting underground fires developed in the United States, and
somewhat similar to the British foam plug. It involves the formation of a
high-expansion noncombustible foam. Large volumes of the foam are drawn or
blown over and around the fire until it can no longer be sustained due to
lack of oxygen. The foam is made from ammonium lauryl sulfate and 1 gal
(3.8 L) of solution is used for each 250 to 300 ft3 /min (7.1 to
8.5 m3 /min) of air passing through the net. Nelson
An explosive that is capable of detonating. There are two main types: (1)
primary explosives, which detonate no matter what type of stimulus is
given--these usually are very sensitive and (2) secondary explosives,
which detonate normally only when the stimulus is a strong shock--under
other types of stimulus they may merely deflagrate.
See:fast gear
The ordinary blast furnace. Fay
a. Said of an ore with a relatively high ore-mineral content.
CF:low-grade
b. To steal rich or specimen ore. AGI
c. An arbitrary designation for dynamite of 40% strength or over.
See also:grade
A plant for treating high-grade ores.
Theft of valuable pieces of ore. See also:gouging
A placer on an alluvial terrace.
Peat occurring on high moors and formed predominantly of moss, such as
sphagnum. Its moisture content is derived from rain water rather than from
ground water and is acidic. Mineral matter and nitrogen content are low,
and cellulose content is high. Syn:moorland peat; moor peat; moss peat.
AGI
Ores containing from 0.18% to 1.0% phosphorus. Newton, 1
See:shaft pillar
Phase of quartz stable from 867 to 1,470 degrees C. Also called beta
quartz. See also:quartz
See:miner
Coals containing less than 4% of moisture in the air-dried coal or more
than 84% of carbon (dry ash-free coal). All other coals are considered as
low-rank coals. BCI