a. The process of cutting a passage through a pillar of coal. CTD
b. N. of Eng. An opening cut into, or a narrow slice taken off, a pillar
in the room-and-pillar system of working coal. A fast junking is a narrow
place driven lengthwise in a pillar of coal, but unholed into the room on
either side of the pillar. A loose junking is a similar place driven along
the side of the pillar and open to the room along that side. Fay
A bit designed to grind or cut foreign metallic material or junk in a
borehole into pieces small enough to be washed out of the hole or
recovered by a basket. CF:milling bit; rose bit. Long
a. Dev. Limestone concretions in slate.
b. Corn. Joints in rocks.
A patented process for making cast steel by melting wrought-steel scrap
with about 2.0% ferrosilicon, up to about 0.5% ferromanganese, and about
3.0% aluminum, then casting in molds of a special composition.
A steel produced by the Jupiter process; it is about as strong and as
ductile as forged steel.
The second period of the Mesozoic Era (after the Triassic and before the
Cretaceous), thought to have covered the span of time between 190 million
years and 135 million years ago; also, the corresponding system of rocks.
It is named after the Jura Mountains between France and Switzerland, in
which rocks of this age were first studied. AGI
Any temporary or makeshift device, rig, or piece of equipment.
Hunt
A small tub or truck used for gathering coal in thin seams. CTD
a. Said of an ore-forming fluid or mineralizer that is derived from a
magma, via fractional crystallization or other plutonic mechanism, as
opposed to fluids of surface, connate, or meteoric origin. AGI
b. A term applied to water and gases that are known to have been derived
directly from magma and are thought to have come to the Earth's surface
for the first time. AGI
c. In the classification of pyroclastics, the equivalent of essential;
derived directly from magma reaching the surface. AGI
Water from the interior of the Earth that is new or has never been a part
of the general system of ground water circulation. CF:magmatic water
See:contact twin
Chromian clinochlore. Alternate spelling of kaemmererite.
A monoclinic mineral, NaCa2 (Mg,Fe)4 Ti(Si6 Al (sub
2) )O22 (OH)2 ; amphibole group with Mg/(Mg+Fe)= 0.5 to 1.0;
forms a series with ferrokaersutite; a typical constituent of alkaline
volcanic rocks.
A tetragonal mineral, Fe(UO2 )2 AsO4 )2
.10-12H2 O ; autunite group; forms lemon-yellow plates; at
Carinthia, Austria.
See:calamine
A steelmaking process in which oxygen is fed into a large inclined
rotating vessel through water-cooled lances, but at velocities somewhat
lower than in the L.D. steel process, so that the jet does not completely
or continuously penetrate the slag layer. In some respects, it is like a
continuously rotating open hearth. It gives better heat utilization than
the L.D. steel process but is slower. Nelson
Eng. Surface-weathered ironstone or oolite; rottenstone; in
Northamptonshire, Rutland, and Lincolnshire. Also spelled keale.
Arkell
A monoclinic mineral, KHMg2 B12 O16 (OH)10 .4H
2 O ; formerly called heintzite, hintzeite, paternoite.
See also:heintzite
See:kalicinite
A monoclinic mineral, KHCO3 ; colorless, white, or yellow. Also
spelled kalicine; kalicite.
A possibly monoclinic mineral, KAl(SO4 )2 .11H2 O .
Syn:potash alum