See:pleochroic halo
a. An unstable isotope of an element that decays or disintegrates
spontaneously, emitting radiation. Lyman
b. Radioisotope is loosely used as a syn. for radionuclide.
See also:radium; radon. Syn:unstable isotope
a. Subclass of the Sarcodina consisting of marine protozoans that possess
complex internal siliceous skeletons.
b. Silica rock formers. Mason
Deposits of siliceous ooze made up largely of radiolarian skeletons and
are formed at depths between 13,000 ft and 25,000 ft (4.0 km and 7.6 km).
AGI
Radio signal unit used to control or communicate between scattered
sections of mine, or to link isolated camp with other places.
Pryor, 3
A spherulite composed of radially arrayed acicular crystals.
A one-shot bore-hole-surveying instrument having the horizontal (compass)
and vertical indicator markings painted with a radioactive substance, such
as that on the luminous dial of a watch. The positions of these markings
are recorded on small, circular, photographic film. Long
a. Said of the texture of an igneous rock characterized by radial, fanlike
groupings of acicular crystals, resembling sectors of spherulites.
AGI
b. Said of limestones in which the components radiate from central points,
with the cement comprising less than 50% of the total rock. AGI
The application of X-rays to the study of the internal structure of
various materials, esp. metals. Fay
Essentially a heat-flow meter used to measure long-wave radiation as well
as solar radiation. It can be used both for daytime and nighttime
measurements and to measure the net heat transfer through a surface.
Hunt
A test to determine contained quantity of uranium. The actual uranium
present may be more or less than the assay shows. See also:equilibrium;
inequilibrium. Ballard
A device for separating gangue from uranium-bearing ore, after primary
crushing. Nelson
Use of portable Geiger-Muller apparatus for field detection of emission
count in search for radioactive minerals. Pryor, 3
An FM apparatus, using the mine haulageway trolley wire for power and
antenna, that permits the dispatcher to talk back and forth with his motor
crews as they are moving throughout the mine. This saves stopping and
starting trips to make telephone calls. Kentucky
See:zeophyllite
An electromagnetic method used in mineral exploration in which a
high-frequency current is used, ranging from 30,000 to 50,000 Hz, but, if
necessary, a frequency as low as 50 to 3,000 Hz, can be made available.
The detecting or direction-finding coil, mounted on a tripod, has the form
of a pair of spectacles and is equipped with an amplifier and head
telephone. When the exciting coil is energized, a current is caused to
flow in the conductor and a secondary electromagnetic field is set up
around the conductor. The detecting coil is affected by both the primary
field from the exciting coil and the secondary field. Lewis
A radioactive metallic element; one of the alkaline-earth metals. Symbol,
Ra. It occurs in pitchblende ore, in carnotite sands, and in all uranium
minerals. See also:radioisotope
A name for lead-206, the stable end-product of the radioactive
disintegration of uranium-238 in the uranium disintegration series.
Natural lead contains 23.6% of lead-206. Symbol, RaG. Syn:uranium-lead
Handbook of Chemistry and Physics, 2
A mixture of black pitchblende, yellow uranotile, and orange gummite.
Schaller
Horizontal distance from the center of rotation of a crane to its hoisting
hook. Nichols, 1
A term used in laying mine track; the calculated radius of an arc that
will connect two pieces of track (at a desired angle of direction from
each other) with a smooth curve section.