An insert of metal with low melting point placed in boilers, sprinklers,
and other devices to melt when the temperature becomes dangerously high,
so that the melting will relieve pressure, allow water flow, or otherwise
tend to alleviate the dangerous condition. Strock, 2
The degree of heat at which any substance begins to melt or liquefy.
See also:melting point
a. A maceral of coal within the inertinite group with intact or broken
cellular structure, a reflectance (except in meta-anthracite) well above
that of associated vitrinite, and a particle size generally greater than
about 50 mu m except when isolated from other macerals. CF:fusain
AGI
b. A constituent showing well-defined cellular structure of wood or
sclerenchyma. The cell cavities vary in size and shape--round, oval, or
elongated. Bogen structure is common. Occurs as discrete lenses, thin
partings or bands, and as small dispersed fragments; is widely
distributed; common. The physical and chemical properties of fusinite vary
only slightly in coals of different rank, and consequently its
technological properties are fairly constant. IHCP
c. The major maceral, or micropetrologic, constituent of fusain. It
consists of wood (xylem or lignified tissue) of which very little is left
but woody tracheids or thick-walled elements so highly carbonized as to
contain only traces of ulmins. A member of the inertite group. AGI
A process of coalification in which fusain is formed. CF:incorporation;
vitrinization. Also spelled: fusainisation. AGI
Fusain and similar material in coal. AGI
a. A union by or as if by a combination of ingredients achieved by
heating, and mixing together. Webster 3rd
b. The union of atomic nuclei to form heavier nuclei, resulting in the
release of enormous quantities of energy when certain light elements
unite. Also called nuclear fusion. CF:fission
See:button test
A method used to remove certain impurities from diamond concentrate with a
particle size of 0.5 to 1.0 mm. The material, mixed with 10 times its
weight of flake caustic soda, is placed in crucibles and put in a furnace
where a temperature of 650 degrees C is maintained for 45 min. After
furnacing, the material is rinsed to remove the caustic soda and boiled in
a glass beaker containing a solution of 1 part hydrochloric acid and 4
parts water. After further rinsing, the diamond, free from satellites, is
dried on a hotplate. Chandler
The stage on heating a clay whúž,he material is changed from the solid to
the liquid state, but complete liquefaction occurs so gradually with most
clays that a fusion range and not a fusion point is obtained.
See also:squotting
A machine designed to use the fusion-piercing mode of producing holes in
rock. Sometimes incorrectly called a jet drill. Syn:jet-piercing drill
Long
The temperature at which melting takes place. Most refractory materials
have no definite melting points, but soften gradually over a range of
temperatures. Harbison-Walker
Igneous rock consolidated from a flowing magma.
See:pyrometric cone equivalent; button test.
a. A coal microlithotype that contains at least 95% fusinite. It is a
variety of inertite. CF:fusain
b. In 1955 the Nomenclature Subcommittee of the International Committee
for Coal Petrology resolved to use this term for the microlithotype
consisting principally of the macerals fusinite, semifusinite, and
sclerotinite. Two varieties of fusite are distinguishable--a fragile and
powdery fusite and a hard consolidated fusite in which the cavities are
filled by various minerals, carbonates, sulfides, kaolin, and other clay
minerals. Widely distributed, but in general not abundant. Occurs in fine
bands and lenses of varying thickness. The soft variety of fusite
concentrates in the very fine particle sizes. Hard fusite distributes
itself in various sizes (depending on the thickness of the original bands
or lenticles in the seam), but not in the fines. This form of fusite is
usually discarded in the middlings and refuse. IHCP
c. A coal microlithotype containing 95% or more fusinite, plus
semifusinite, plus sclerotinite. Schieferdecker; AGI
A type coal rock consisting of the macerals fusinite and vitrinite; it may
contain all other macerals. Fusinite is present in a smaller quantity than
in clarofusain. CF:clarofusain
a. Durain in which much of the microconglomeratic elements consist of
fusain. AGI
b. Judged obsolete by the Heerlen Congress of 1935. AGI
a. Preferred. Coal consisting of material transitional between fusain and
vitrain with vitrain being predominant (Heerlen Congress of 1935).
CF:vitrofusain
b. Coal consisting of a mixture of vitrain with fusain fragments.
AGI
See:fusulinid
Any foraminifer belonging to the suborder Fusulinina, family Fusulinidae,
characterized by a multichambered elongate calcareous microgranular test,
commonly resembling the shape of a grain of wheat. Range, Ordovician to
Triassic. Syn:fusuline
See:possible ore
Billions of years before the present. AGI