A curved surface in a quaternary system, representing the intersection of
two primary phase volumes, one or both of which are solid solution series.
It is the bivariant equivalent of the univariant cotectic line in ternary
systems. AGI
Eng. To mat together; to entangle. Frequently applied to a hard,
crossgrained, tough stone or coal, as cottered coal.
A variety of quartz having a peculiar metallic pearly luster.
Standard, 2
See:ulexite
An obsolete syn. of chalky chert.
a. A term used in Missouri for a soft, fine-grained, siliceous, white to
slightly gray or buff magnesian limestone having a chalky or porous
appearance suggestive of cotton. AGI
b. The white or light-colored decomposed exterior surrounding the dense
black interior of a chert nodule. AGI
A variety of mesolite. See also:mesolite; cotton rock. Fay
This instrument applies the veiling brightness method of producing
threshold conditions. When in use the sighting telescope is directed
toward some critical detail of the visual task and the veiling brightness
is adjusted until it matches the background. The gradient filter is then
turned until the target detail is at threshold visibility.
Roberts, 2
In ore dressing, smelting, and refining, one who recovers magnesium dust
particles remaining in magnesium gas after processing, using a battery of
Cottrell electrical precipitators. Also called agglomerator operator; dust
operator. DOT
An electrostatic device whereby negatively charged dust or fume particles
are attracted to a positively charged wire electrode enclosed in a flue,
the walls of which act as the other electrode. Widely used for treating
sulfuric acid mist, cement mill dust, power-plant fly ash, metallurgical
fumes, etc. CCD, 2
An orthorhombic mineral, PbCl2 ; soft; acicular crystals.
a. A term applied in the Western United States to a small stream, often
intermittent. Also, the bed of such a stream when dry. AGI
b. A term applied in the Northwestern United States to a dry or
intermittent stream valley, gulch, or wash of considerable extent; esp. a
long, steep-walled, trenchlike gorge or valley representing an abandoned
overflow channel that temporarily carried meltwater from an ice sheet,
e.g., the Grand Coulee (formerly occupied by the Columbia River) in
Washington State. AGI
c. A small valley or a low-lying area. Etymol: French coulee, flow or rush
of a torrent. Pron: koo-lee. Syn:coulie
d. A tonguelike mass of debris moved by solifluction (Monkhouse, 1965, p.
81). AGI
e. A flow of viscous lava that has a blocky, steep-fronted form. Also
spelled: coulee. AGI
A lake produced by the damming of a water course by lava. AGI
See:coulee
The attraction between ions of opposite electric charges. AGI
a. The dissipation of energy that occurs when a particle in a vibrating
system is resisted by a force whose magnitude is a constant independent of
displacement and velocity, and whose direction is opposite to the
direction of the velocity of the particle. Also called dry friction
damping. Hunt
b. See:specific damping capacity
An isometric mineral, Fe2+ V3+2 O4 ;
spinel group; a source of vanadium; formerly called vanado-magnetite.
A high-speed device for particle size analysis designed by W.H. Coulter
and now made by Coulter Electronics, Inc., Chicago. A suspension of the
particles flows through a small aperture having an immersed electrode on
either side with particle concentration such that the particles traverse
the aperture substantially one at a time. Each particle, as it passes,
displaces electrolyte within the aperture, momentarily changing the
resistance between the electrodes and producing a voltage pulse of
magnitude proportional to practical volume. The resultant series of pulses
is electronically amplified, scaled, and counted. Dodd
a. A gangway driven obliquely upwards on a coal seam from the main gangway
until it cuts off the faces of the workings, and then continues parallel
with the main gangway. The oblique portion is called run.
b. A crossvein.
c. An instrument for the detection of uranium and thorium. Nelson
d. A term used for any device that registers radioactive events, i.e.,
alpha counter, beta counter, Geiger-Mueller counter, scintillation
counter. The term is correctly used only for devices that actually
register number of events, but is often erroneously applied to count rate
meters that register events per unit time.
e. An apparatus for recording the number of strokes made by a pump, an
engine, or other machinery.
Drilling or boring a flatbottomed hole, often concentric with other holes.
Syn:counterflush boring; reversed flush boring. ASM, 1
A chute through which the coal from counter-gangway workings is lowered to
the gangway below. Fay