See:chews.
A butyraceous, greenish-yellow to wax-yellow hydrocarbon from Wettin,
Saxony, Germany. It has a specific gravity of less than 1 and is soft at
55 to 60 degrees C. Fay
In optical mineralogy, a dispersion phenomenon in which the boundary of a
mineral grain (Becke line) immersed in a liquid of the same index of
refraction appears blue on one side and red to orange on the other.
See also:dispersion
See:cristobalite
A salt or ester of chromic acid; a compound containing the radical (CrO
4 )2- . AGI
In microscope lenses, the splitting of white light to form two images, one
red and the other blue. See also:aberration
A hue, as distinguished from white, black, or any tone of gray. Opposite
of achromatic color.
A tetragonal mineral, CaCrO4 ; forms finely crystalline
citron-yellow crusts from clefts in limestones.
An instrument for analyzing gases and vapors from liquids with boiling
points up to 300 degrees C. The gas chromatograph often arranges the
molecules of a gas in increasing size, and as each group emerges from the
column, a detector measures the quantity of each. Since all the molecules
of one type emerge after the same time interval, it is possible to
identify quickly the constituents present. Nelson
Separation of components of mixture into zones, one or more of which can
be identified by color, etc.: (1) by adsorption column, adsorbing from
solute in a tube packed with cellulose, alumina, lime, etc.; (2) by
electrochromatography, passing electricity across a column or paper strip
down which solvent mixture is flowing, causing migration to the side of a
flow line; (3) by electrophoresis, using electric current to aid
migration; and (4) by paper partition, separation into bands as suitable
solvent flows past a drop of solution, which contains compounds
(qualitative and quantitative analysis). Pryor, 3
A chemical process of separating closely related compounds by permitting a
solution of them to filter through an absorbent so that the different
compounds become absorbed in separate colored layers comprising a
chromatogram. Hunt
A term commonly used to indicate ore of chromium, consisting esp. of the
mineral chromite or chromium-bearing minerals, such as chrome mica or
chrome diopside. AGI
A variety of antigorite containing some chromium.
A refractory brick manufactured substantially or entirely of chrome ore.
ASTM
A variety of chert that has replaced the silicate minerals of a chromite
peridotite, the more resistant chromite grains remaining unaltered in the
siliceous matrix. Holmes, 2
a. A variety of diopside. Dark-green specimens are seldom either
transparent or cut as gems.
b. A bright emerald-green variety of diopside containing a small amount of
Cr2 O3 .
See:uvarovite
An emerald-green variety of vesuvianite containing chromium; occurs at
Black Lake, Quebec, Canada; and Ekaterinburg, Ural Mountains, Russia.
Syn:chrome vesuvian
See:chromite
See:fuchsite