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gram-centimeter

A unit of work; the work done in raising the weight of 1 g vertically 1
cm; 981 ergs. Standard, 2

gram-molecule

Molecular weight of a compound in grams, derived from that of hydrogen
which, though 2.016, is expressed as the whole number 2. The
gram-molecule, e.g., of H2 SO4 is 2 + 32 + (4 x 16) = 98.
Also called mole. Pryor, 3

grampus

The tongs with which bloomery loups and billets are handled. Fay

gram weight

Pull of gravitation on a mass of 1 g. This varies slightly with the
acceleration (g) due to gravity differences in various localities, but is
approx. 981 dyn. Pryor, 3

granat

See:garnet

Granby car

A type of automatically dumped car for hand- or power-shovel loading. In
this type of car, a wheel attached to the side of the car body engages an
inclined track at the dumping point. As the side wheel rides up and over
the inclined track, the car body is automatically raised and lowered,
activating a side door operating mechanism which raises the door,
permitting the car to shed its load. See also:mine car
Pit and Quarry

grandite

The grossular-andradite series of the garnet group.

granite

a. A plutonic rock in which quartz constitutes 10% to 50% of the felsic
components and in which the alkali feldspar/total feldspar ratio is
generally restricted to the range of 65% to 90%. Rocks in this range of
composition are scarce, and sentiment has been growing to expand the
definition to include rocks designated as adamellite or quartz monzonite,
which are abundant in the United States. AGI
b. Broadly applied, any holocrystalline, quartz-bearing plutonic rock.
Syn:granitic rock
c. Commercial granite. AGI

granite gneiss

a. A gneiss derived from a sedimentary or igneous rock and having the
mineral composition of a granite. AGI
b. A metamorphosed granite. AGI

granite porphyry

A hypabyssal rock differing from a quartz porphyry by the presence of
sparse phenocrysts of mica, amphibole, or pyroxene in a medium- to
fine-grained groundmass. AGI

granite tectonics

The study of the structural features, such as foliation, lineation, and
faults, in plutonic rock masses, and the reconstruction of the movements
that created them. AGI

granite wash

A driller's term for material eroded from outcrops of granitic rocks and
redeposited to form a rock having approx. the same major mineral
constituents as the original rock; e.g., an arkose consisting of granitic
detritus. AGI

granitic

Pertaining to or composed of granite. Syn:granitoid
See also:granular texture

granitic layer

See:sial

granitic rock

A term loosely applied to any light-colored, coarse-grained plutonic rock
containing quartz as an essential component, along with feldspar and mafic
minerals. Syn:granite

granitification

See:granitization

granitization

An essentially metamorphic process by which a solid rock is converted into
a granitic rock by the entry and exit of material, without passing through
a magmatic stage. Some authors include in this term all granitic rocks
formed from sediments by any process, regardless of the amount of melting
or evidence of movement. The precise mechanism, frequency, and magnitude
of the processes are still in dispute. Syn:granitification
CF:transfusion

granitizer

See:transformist

granitoid

See:granitic

granoblastic

Pertaining to a homeoblastic type of texture in a nonschistose metamorphic
rock upon which recrystallization formed essentially equidimensional
crystals with normally well sutured boundaries. Syn:granular
CF:crystalloblastic

granodiorite

A group of coarse-grained plutonic rocks intermediate in composition
between quartz diorite and quartz monzonite (U.S. usage), containing
quartz, plagioclase (oligoclase or andesine), and potassium feldspar, with
biotite, hornblende, or, more rarely, pyroxene, as the mafic components;
also, any member of that group; the approximate intrusive equivalent of
rhyodacite. The ratio of plagioclase to total feldspar is at least 2:1 but
less than 9:10. With less alkali feldspar it grades into quartz diorite,
and with more alkali feldspar, into granite or quartz monzonite.
AGI