See:clastic rock
a. A general textural term applied to rocks composed of fine materials or
of sandy, conglomeratic, bouldery, and brecciated materials. The texture
of clastic rocks. AGI
b. A texture of sedimentary rocks, characterized by broken, abraded, or
irregular particles in surface contact, and resulting from the physical
transport and deposition of such particles; the texture of a clastic rock.
The term is used in distinction to a crystalline texture. AGI
c. The texture of a pyroclastic rock, such as a tuff or volcanic breccia.
AGI
a. The breakage of rock during blasting in which explosive energy
fractures the solid mass into pieces; the distribution of rock particle
sizes after blasting. See also:degradation
b. Index of the degree of breaking up of rock after blasting.
Fraenkel
A texture in which pellets form spheroidal aggregates resembling a
raspberry.
a. In trench excavations requiring timbering, the struts separating the
boards, together with the walings, which they hold, form a frame.
Hammond
b. Eng. A table composed of boards slightly inclined, over which runs a
small stream of water to wash off waste from slime tin; a buddle. Also
called rack. Fay
Eng. A solid, watertight stopping or dam in a mine to keep back and resist
the pressure of a heavy head of water.
A barrier, generally built of timber framed to form a water face,
supported by struts. Seelye, 1
The legs and cap or crossbar arranged so as to support the roof of an
underground passage. Also called framing; set. Fay
A variety of black bort from South Africa showing minute brilliant points
possibly due to included diamonds. CF:bort
An inclined table used in separating ore slimes by running water; a
miner's frame. Standard, 2
A traveling-belt screen in which the screen cloth is mounted on a series
of separate pallets, thus avoiding bending the screen as it goes over the
pulleys. Liddell
An orthorhombic mineral, (Ba,Pb)(UO2 )2 (VO4 ) (sub
2) .5H2 O ; forms a series with curienite; occurs as yellow
impregnations in sandstone; from Franceville, Gabon.
Jurassic to Early Cretaceous rocks, characteristic of the Pacific coastal
ranges of California, composed primarily of sandstones, cherts,
serpentinites, and glaucophane schists. The Franciscan should not be
visualized as a formation or sequence with ordinary physical, spatial, and
temporal coherence, but rather as a disorderly assemblage of various
characteristic rocks that have undergone unsystematic disturbance; a
melange. The formation includes deep-water sediments and mafic marine
volcanic material, locally accompanied by masses of serpentinite.
A furnace for the treatment of roasted blende and other fine ore. It
consists of a series of superimposed muffles formed by arches of magnesia
brick and built into the walls of the furnace and communicating with a
common condensation chamber. Fay
A triclinic mineral, (Pb,Sn)6 FeSn2 Sb2 S14 ;
forms imperfect, radiated folia. Occurs at Poopo, Llallagua, and several
other tin districts of Bolivia; at Coal River, UT; in Canada; and in Inyo
and Santa Cruz Counties, CA.
The cementation sinking method. The process was introduced into Great
Britain in 1911. See also:cementation sinking
An isometric mineral, BaF2 ; fluorite group.
An isometric mineral, 8[ZnFe2 O4 ] ; magnetite series;
spinel group; forms metallic black octahedra with rounded edges; weakly
ferrimagnetic; a source of zinc at the Franklin and the Sterling Hill
deposits, NJ.
a. A process for mining native sulfur, in which superheated water is
forced into the deposits for the purpose of melting the sulfur. The molten
sulfur is then pumped to the surface. AGI
b. A desulfurizing process that consists of distilling oil over lead
oxide, followed by refining with sulfuric acid. See also:sulfur mining
Fay
Native sulfur mined by the Frasch hot-water process. USBM, 7
A dense-media process in which a dry, specific-gravity separation of coal
from refuse is achieved by utilizing a flowing dense medium intermediate
in density between coal and refuse. The dense medium is formed by bubbling
air through a mass of dry sand, 30 to 80 mesh in size. The air dilates and
fluidizes the sand mass, causing it to behave somewhat as a heavy liquid.
The coal floats on the aerated sand mass and the refuse sinks.
Syn:air-sand process