A sinusoidal quantity having a frequency that is an integral multiple of
the frequency of a periodic quantity to which it is related. Hy
A crystal designed to oscillate at an integral multiple of its fundamental
frequency. Am. Mineral., 2
Folding in which the strata remain parallel or concentric, without
structural discordances between them, and in which there are no sudden
changes in the form of the folds at depth. Ant: disharmonic folding.
AGI
A monoclinic mineral, (Ba,K)1-2 (Si,Al)8 O16 .6H (sub
2) O ; zeolite group; in hydrothermal veins, vugs in igneous rocks,
manganese ores, saline lakes. Syn:cross-stone
a. A large, sickle-shaped igneous intrusion that was injected into
previously deformed strata and was subsequently deformed with the host
rock by horizontal stretching or orogenic forces. AGI
b. Essentially a phacolith with a vertical axis. AGI
Scot. To rob; to take all the coal that can conveniently be mined without
attempting to systematically remove the whole. A variation of harry; to
strip; despoil; to rob. Fay
Trammers, putters, or drawers employed to convey trucks or tubs from the
working face. They may help load the trucks. CTD
a. Chalcocite pseudomorphous after galena. Holmes, 2
b. A phanerocrystalline rock composed essentially of black, lustrous,
cleavable olivine with anorthite and a little augite. Holmes, 2
Process for removing arsenic, antimony, tin, and zinc from virgin or
secondary lead by agitating the molten metal with molten caustic soda and
salt. All undesirable metals are oxidized, and the oxides are dissolved in
the caustic, with the exception of silver, which is removed in a
subsequent desilvering operation. CCD, 2
Hard chalk. Arkell
A pole with teeth in it, which revolves in a puddling trough to puddle
auriferous clay. Gordon
See:hartite
Hydrocarbon occurring in brown coal as transparent masses or small, waxy
triclinic crystals. Syn:hartine; josen. Tomkeieff
An early form (1932) of stable gravimeter consisting of a weight suspended
from a spiral spring, a hinged lever, and a compensating spring for
restoring the system to a null position. AGI
A variety of oil shale from Hartley, New South Wales. Tomkeieff
Hard salt, a mixture of sylvinite and kieserite, with some anhydrite,
found in the Stassfuert salt deposits Kaufmann
A strongly banded and partly schistose rock; associated with other rocks
of mylonitic habit, in which the alternating bands have been produced from
ultramylonite by recrystallization and metamorphic differentiation.
Holmes, 2
Method of carburizing the surface layers of low-carbon steel, followed by
rapid chilling. Pryor, 3
A variety of peridotite that consists essentially of olivine and enstatite
or bronzite.
A jig in which pulsion is given intermittently with suction; the periods
devoted to them are about equal. See also:hodge jig; jig.
Liddell
This type of turntable is used as an alternative to the shunt-back or the
traverser for changing the direction of mine cars or tubs, either on the
surface or underground. A pulley driven by a creeper chain bringing along
the cars is on the same vertical axis as the turntable and is so disposed
that when a car is on the table two of its wheels rest on its central
pulley while the other two rest on the outer edge of the turntable.
Sinclair, 5