a. A fossil resin found in and in association with lignite beds of Eocene
age. Commonly occurring in many European localities, and is esp. abundant
in areas bordering the Baltic coast. See also:amber
b. German name for amber. Tomkeieff
A monoclinic mineral, (Fe2+ ,Fe3+ ,Mg)2-2D3
(Si,Al)2 O5 (OH)4 of the kaolinite-serpentine group;
dark steel-gray; in low-temperature vein deposits.
Syn:martourite
A discredited name for bournonite.
An orthorhombic mineral, 4[Be4 Si2 O7 (OH)2 ];
colorless to clear pale yellow and shows heart-shaped twins; in
pegmatites; a source of beryllium. See also:beryllium disilicate
A removable lens in the tube of a polarized-light microscope used to
converge light to form an interference figure.
A heavy-fluid coal cleaning process that utilizes a calcium chloride
solution as separating medium and is applicable only to deslimed feed. It
differs from the Lessing process in that the raw coal is introduced into
the system countercurrent fashion, from water to separating solution, the
purified coal and the waste being withdrawn in a similarly countercurrent
fashion. Coal containing less than 1% ash is said to be obtained by this
process. Gaudin, 1
A hexagonal mineral, Be3 Al2 Si6 O18 ; green,
blue-green, and other pale tints; in granite pegmatites, mica schists, and
an accessory mineral in felsic igneous rocks; the chief source of
beryllium. Transparent and colored gem varieties include emerald,
aquamarine, morganite, heliodor, golden beryl, bixbite, and vorobievite.
A group of intermetallic compounds of potential interest as special
ceramics. Cell dimensions and types of structure have been reported for
the beryllides of titanium, vanadium, chromium, zirconium, niobium,
molybdenum, hafnium, and tantalum. Dodd
An occupational disease caused by the inhalation of fumes liberated during
the reduction of beryllium. Beryllium is thought to play the principal
role, aggravated by fluorine, and to affect all organs, particularly the
larger protective glands, rather than the respiratory apparatus alone.
Hess
A hydrous silicate of beryllium, Be3 SiO4 (OH)2 .H
2 O , as an alteration product of epididymite. Spencer, 5
An element belonging to the alkaline earth metals. Symbol, Be. Beryl and
bertrandite are the most important commercial sources of the element and
its compounds. Aquamarine and emerald are the precious forms of beryl.
Used in nonsparking tools, high-speed aircraft, missiles, spacecraft,
communications satellites, and X-ray lithography for microminiature
integrated circuits, as well as in nuclear reactors and computers.
Beryllium and its salts are toxic.
BeAl2 O4 ; mol wt, 126.97; orthorhombic; sp gr, 3.76; source
of beryllium. Syn:chrysoberyl
Be2 C ; decomposes above 2,950 degrees C. Used as a moderator in
nuclear application. Molecular weight, 30.04; yellow; hexagonal; and sp
gr, 1.90 at 15 degrees C. Lee; Bennett
Be4 Si2 O7 (OH)2 ; mol wt, 238.23;
orthorhombic; sp gr, 2.6. Syn:bertrandite
Be3 N2 ; molecular weight, 55.05; colorless; isometric; and
melting point, 2,200 + or - 100 degrees C. Bennett
A white powder; hexagonal; BeO. Used in the preparation of beryllium
compounds and in ceramics and refractories. Melting point, 2,570 degrees
C; and sp gr, 3.02. Bodies high in BeO have extremely high thermal
conductivity (in the range of metals) and also possess high mechanical
strength. Used in nuclear reactors because of its refractoriness, high
thermal conductivity, and ability to act as a moderator for fast neutrons,
reducing them to thermal speeds. Beryllia ceramics are used for electronic
components and for crucibles for melting uranium and thorium.
Syn:bromellite
A monoclinic mineral, NaBePO4 ; colorless or yellow; forms
transparent, topazlike pseudo-orthorhombic crystals.
In crystallography, the dihexagonal bipyramid, common in crystals of
beryl.
See:emerald glass
beryl preferential stain process
A quick, simple method for determining the amount of beryl in a mineral
sample. The samples are placed in a hot solution of sodium hydroxide,
which etches the beryl grains in the sample; they then are stained an
intense blue with another reagent to enable counting under a microscope.
An isometric mineral, Cu2 Se ; silver-white in fresh break; sp gr,
6.7. ; dimorphous with bellidoite.