A group of dark-colored, basic intrusive igneous rocks composed
principally of basic plagioclase (commonly labradorite or bytownite) and
clinopyroxene (augite), with or without olivine and orthopyroxene; also,
any member of that group. It is the approximate intrusive equivalent of
basalt. Apatite and magnetite or ilmenite are common accessory minerals.
AGI
Said of a rock resembling gabbro. AGI
See:mine car
An orthorhombic mineral, PbFe(AsO4 )(OH) ; adelite group; forms
black adamantine lumps at Laangban, Sweden.
A heavy steel wedge, 6 in or 8 in (15.2 cm or 20.3 cm) long, with a narrow
chisel point for cutting samples or breaking out pieces of loose rock.
Hess
In quarrying, a small car or platform carrying a drilling machine, so as
to make a straight line of holes along its course in getting out dimension
stone. Also called gadding car. Syn:gadding machine
Standard, 2
See:gadder
a. A monoclinic mineral, (Y,Ce,La,Nd)2 Be2 Si2 O (sub
10) ; further speciated according to the predominant rare-earth element;
weakly radioactive; occurs with fluorite, allanite, and beryl in granites
and granite pegmatites; with xenotime in biotite gneisses.
b. The mineral group bakerite, datolite, gadolinite-(Ce), gadolinite-(Y),
hingganite-(Ce), hingganite-(Y), hingganite-(Yb), homilite, and
minasgeraisite-(Y).
Jetlike coalified plant material preserving cellular structures.
See also:gagatization
In coal formation, the impregnation of wood fragments with dissolved
organic substances. See also:gagatite
a. Spacing of tracks or wheels. Nichols, 1
b. The nominal size of an aggregate. It is the minimum size of sieve
through which at least 95% of an aggregate will pass. Also spelled gauge.
Taylor
A small cock in a boiler at the water line, to determine the water level.
A wooden door fixed in an airway for regulating the supply of ventilation
necessary for a certain district or number of workers. Also called a
regulator.
The percentage charge of resistance divided by the percentage strain. For
strain gages in common use, this amounts to about 2.2. Issacson
The diametrical reduction in the size of a bit or reaming shell caused by
wear through use. Long
In the iron and steel industry, one who determines whether iron or steel
bars, sheets, or wire are being rolled to plant specification, so that the
rolls may be adjusted to reduce the metal the desired amount for each
pass, using calipers to check the thickness (gage) of the various
products. DOT
The width of a drill bit along the cutting edge. Nichols, 1
Any one of several diamonds set in the crown of a diamond bit in a plane
parallel with and projecting slightly beyond the inside and/or outside
walls of the bit. Syn:kicker; kicker stone; reaming diamond.
CF:cutting stones
A heap of rubbish placed at the entrance of a disused roadway underground.
CTD
A particular site on a stream, canal, lake, or reservoir where systematic
observations of gage height, discharge, or water quality (or any
combination of these) are obtained. AGI
An isometric mineral, ZnAl2 O4 ; spinel group; forms series
with spinel and with hercynite; Mohs hardness, 7-1/2; forms octahedra or
masses in schists, contact-metamorphosed limestones, granite pegmatites;
relatively common in replacement ores at Franklin, NJ, and Falun, Sweden.
Syn:zinc spinel