See:zaratite
An assembled stone commonly consisting of a crown and pavilion of rock
crystal bound together by transparent green cement or a thin piece of
green sintered glass; immersed in water and viewed sideways, the top and
bottom are colorless with a line of color along the girdle. Green or
colorless beryl may be used for the crown and possibly for the pavilion.
Glass may be used for the pavilion, and sometimes for the crown as well,
but the trade still calls it an emerald triplet. Syn:Soude emerald
See also:tripletine
A misnomer for dioptase.
a. A change in the levels of water and land such that the land is
relatively higher and areas formerly under water are exposed; it results
either from an uplift of the land or from a fall of the water level. Ant:
submergence. AGI
b. The point where an underground stream appears at the surface to become
a surface stream. Syn:resurgence; rise; rising. AGI
An impure mineral of the corundum or aluminum oxide type used extensively
as an abrasive before the development of electric-furnace products.
See also:emery rock
A granular rock that is composed essentially of an impure mixture of
corundum, magnetite, and spinel, and that may be formed by magmatic
segregation or by metamorphism of highly aluminous sediments. Syn:emery;
corundolite. AGI
A variety of spessartine garnet, with yttrium substituting for manganese
up to 2%, in pegmatites at Elk Mountain, NM. See:spessartine
See:emildine
Monochromatic light from quantized electron transitions in thermally
excited ions or atoms. CF:absorption spectra
A spectrum regarded as characterizing the body that emits the rays rather
than one through which they pass. Standard, 2
The maximum amount of pollutant permitted to be discharged from a single
polluting source. NSC, 1
The ratio of radiant energy emitted by a body to that emitted by a perfect
black body. A perfect black body has an emissivity of 1; a perfect
reflector an emissivity of 0. Strock, 2
A triclinic mineral, Fe2 (TeO3 )3 .2H2 O ; in
yellow-green microcrystalline masses, fibrous crusts, patches of minute
acicular crystals, or thin scaly coatings in the oxidation zones of gold
and silver telluride districts of North and Central America.
A chute with narrow opening for the cleaning of coal. The slate, traveling
slowly because of friction, falls into the openings and thus is removed
from the coal, which, rolling freely down the incline, is carried over the
narrow gap. Zern
a. A light, hand-operated churn drill for testing placers from 10 to 125
ft (3.0 to 38.1 m) deep, though it is more commonly used for shallower
holes. It consists of a string of 4-in (10.2-cm) casing, to the lower end
of which is screwed a toothed cutting shoe. To the upper part, projecting
above the ground, is fastened a round steel platform on which workers
stand while operating the drilling tools. The casing can be turned by
workers or a horse on the end of a long sweep fastened to the platform.
The core of material inside the casing is loosened and brought to the
surface by a drill pump on the end of a string of rods. CF:Banka drill
Lewis
b. A term often misused as a synonym for churn drill. Long
A process by which igneous rock intrudes, or an orebody is formed in older
rocks. AGI
An orthorhombic mineral, CuBiS2 ; metallic, grayish to tin-white,
acicular to prismatic crystals with longitudinal striations; sp gr, 6.3 to
6.5; associated with chalcopyrite and other sulfides in silver veins or
bismuth-rich parts of contact metamorphic deposits; may be confused with
bismuthinite.
See:emplectite
An orthorhombic mineral, AgTe ; forms fine granular, pale-bronze masses;
sp gr, 7.61; associated with galena and native tellurium at the Empress
Josephine Mine, Kerber Creek district, CO.
An empty car, truck, tub, box, or wagon. Mason
In bituminous coal mining, a laborer who pulls empty cars from cage or
detaches them from hoisting cable when hoisting of loaded cars is done on
one side of the shaft or haulage slope and lowering is done on the other.
DOT