Liquid used to displace captured ions from the zeolite or resin on which
they are held; also, in ion exchange processes, solution used for elution.
In chromatography, the solution used to displace absorbed substances.
Pryor, 3
a. A method of mechanical analysis of a sediment, in which the finer,
lightweight particles are separated from the coarser, heavy particles by
means of a slowly rising current of air or water of known and controlled
velocity, carrying the lighter particles upward and allowing the heavier
ones to sink. AGI
b. Purification, or removal of material from a mixture or in suspension in
water, by washing and decanting, leaving the heavier particles behind.
Syn:water separation
An appliance for washing or sizing very fine particles, based on the
principle that large grains settle at a faster rate through a liquid than
small grains of the same material. The medium is commonly an upward
current of water. See also:hydraulic classifier; Stokes' law.
Nelson; Pryor, 3
a. Said of an incoherent mineral deposit, such as a placer, resulting from
the decomposition or disintegration of rock in place. The material may
have slumped or washed downslope for a short distance but has not been
transported by a stream. AGI
b. Pertaining to eluvium; residual. AGI
a. An accumulation of rock debris produced in place by the decomposition
or disintegration of rock; a weathering product; a residue. AGI
b. Fine soil or sand moved and deposited by the wind, as in a sand dune.
CF:alluvium
Cornish term for pneumatolized granite rocks containing tourmaline,
fluorite, or topaz. Pryor, 3
See:emildine
An ore deposit of gaseous magmatic origin.
A linear structure, usually of earth or gravel, constructed so as to
extend above the natural ground surface and designed to hold back water
from overflowing a level tract of land, to retain water in a reservoir,
tailings in a pond, or a stream in its channel, or to carry a roadway or
railroad; e.g., a dike, seawall, or fill. AGI
a. Penetration of microcrystalline groundmass material into phenocrysts,
making their normal euhedral boundaries incomplete. An irregular corrosion
or modification of the outline of a crystal by the magma from which it
previously crystallized or in which it occurs as a foreign inclusion; esp.
the deep corrosion into the sides of a phenocryst. The penetration of a
crystal by another, generally euhedral, crystal. Such a crystal is called
an embayed crystal. AGI
b. A downwarped area containing stratified rocks, either sedimentary or
volcanic or both, that extends into a terrain of other rocks, e.g., the
Mississippi Embayment of the U.S. Gulf Coast. AGI
a. Sectile, ductile; occurs as gray, yellowish or greenish-gray hornlike
masses, waxy coatings, or crusts, as a secondary mineral in the oxidized
zone of silver deposits; commonly associated with native silver, manganese
oxides, and secondary lead and copper minerals.
b. The chief source of silver in some Chilean mines occurring as
yellow-green incrustations and masses. It occurs in Australia at Broken
Hill, New South Wales, and at Silver Reef, Victoria; widespread in the
silver mining districts of the United States. Syn:horn silver
Reduction in the normal ductility of a metal because of a physical or
chemical change. ASM, 1
a. A brilliant green gem variety of beryl, highly prized as a gemstone.
The color, which is caused by chromium or vanadium impurity, ranges from
medium-light to medium-dark tones of slightly bluish green to slightly
yellowish green. Syn:smaragd
b. Any of various gemstones having a green color; e.g., oriental emerald
(sapphire), copper emerald (dioptase), Brazilian emerald (tourmaline), or
Uralian emerald (demantoid variety of andradite garnet).
c. Said of a gemmy and richly green-colored mineral; e.g., emerald jade
(jadeite), emerald spodumene (variety hiddenite), or emerald malachite
(dioptase).
See:dioptase
A step cut in which the finished gem is square or rectangular and the rows
(steps) of elongated facets on the crown and pavilion are parallel to the
girdle with sets on each of the four sides and in some cases at the
corners; commonly used on diamonds to emphasize the absence of color and
on emeralds and other colored stones to enhance the color. CF:step cut
See:emerald glass
The trade name for a color filter through which genuine emeralds and some
other genuine stones appear reddish to violetish while glass imitations
and some genuine stones appear greenish. Syn:beryloscope
See also:Walton filter
A misnomer for chalcedony stained green with chromic oxide. It is a deeper
green than nickel-stained chalcedony and, unlike the nickel types, shows a
red residual color under the dichromatic filter.
Semitransparent to translucent jadeite of emerald color.
Syn:imperial jade
See:Walton filter
See:dioptase