Elemental sulfur produced from hydrogen sulfide obtained from sour natural
gas, petroleum refinery gas, water gas, and other fuel gases.
a. The percentage of valuable constituent derived from an ore, or of coal
from a coal seam; a measure of mining or extraction efficiency.
AGI
b. The ratio of the footage of core acquired from core drilling a specific
length of borehole, expressed in percent. Long
c. The carat weight of diamonds salvaged from a worn bit. Long
a. A plant designed for separating diamond particles from concentrate by
various processes, usually including grease belts, jigs, electrostatic
separators, and flotation. Also known as picking station.
b. The processing facility where minerals are recovered.
Mining as an avocation rather than as a business. Barton
The formation, essentially in the solid state, of new crystalline mineral
grains in a rock. The new grains are generally larger than the original
grains, and may have the same or a different mineralogical composition.
AGI
recrystallized silicon carbide
A refractory made of about 98% to 99% SiC.
A drainage pattern in which the main streams and their tributaries display
many right-angle bends and exhibit sections of approx. the same length; it
is indicative of streams following prominent fault or joint systems that
break the rocks into rectangular blocks. AGI
A shaft excavated to an oblong shape. The majority of shafts sunk in the
Republic of South Africa before 1948 were rectangular and timber lined.
The shape lends itself to equipping concurrently with sinking; it provides
a convenient in-line hoisting arrangement and can easily be divided into
separate compartments. However, in the 1950's and 1960's developments were
towards the concrete lined circular shaft. See also:compartment
Nelson
a. The process by which electric energy is transferred from an
alternating-current circuit to a direct-current circuit.
Coal Age, 1
b. The purification of a liquid by redistillation. CTD
c. In electronics and signal processing, the transformation of a signal
from an alternating positive and negative signal into an all-positive
signal by taking its absolute value.
Equipment used in mines to convert alternating current to direct current.
An elementary device consisting of one anode and its cathode that has the
characteristic of conducting current effectively in only one direction.
Coal Age, 1
A clay mineral with regularly interstratified mica and smectite layers.
Syn:allevardite
An overturned fold, the axial surface of which is horizontal or nearly so.
a. A continuous heat exchanger in which heat is conducted from the
products of combustion to incoming air through flue walls. ASTM
b. A system of thin-walled refractory ducts used for the purpose of
transferring heat from a heated gas to colder air or gas.
Harbison-Walker
c. Preheating equipment for recovering sensible heat from hot spent gases
from a furnace and using it for heating incoming charge or fuel gases;
essentially, a low-pressure heat exchanger. Syn:regenerative heating
Henderson
A layer of peat marking a sharp change in the character of the peat and
resulting from a profound change in climate. Tomkeieff
See:kermesite
See:realgar
Sedimentary strata composed largely of sandstone, siltstone, and shale,
with locally thin units of conglomerate, limestone, or marl, that are
predominantly red in color due to the presence of ferric oxide (hematite)
usually coating individual grains; e.g. the Permian and Triassic
sedimentary rocks of western United States, and the Old Red Sandstone
facies of the European Devonian. AGI
The vanadium concentrate in a milling operation. Ballard
Hematite mixed with clay.
A brown to red deep-sea deposit, which usually contains manganese nodules
or a film of manganese. It is the finest divided clay suspension that is
derived from the land and transported by ocean currents, accumulating far
from land and at the greatest depths. It has a high proportion of volcanic
material due to lesser dilution of this material owing to slowness of
accumulation of the clay portion. The color is believed to be caused by
oxidation. Syn:brown clay