Removal of tree stumps before excavation starts on a construction site.
Hammond
A hole drilled to a slightly larger diameter than the bolt passing through
it. The clearance for black bolts is normally 1/16 in (1.6 mm).
Hammond
Transparent muscovite without stains and with a smooth surface in
reflected light.
The clear unobstructed distance between the inner extremities of the two
supports of a beam. This dimension is always less than the effective span.
See also:effective span
a. Term applied to systems of joints, cleavage planes, or planes of
weakness found in coal seams along which the coal fractures.
See also:facing; face cleat; bord; butt cleat. Also spelled cleet.
b. Main joint in a coal seam along which it breaks most easily. Runs in
two directions, along and across the seam. Pryor, 3
c. Joints in coal more or less normal to the bedding planes.
BS, 11
d. An attachment fastened to a conveying medium to help propel material
along the path of travel.
York. Crystalline mineral matter, often ankerite, occurring in the cleat
cracks of coal. Arkell
a. The breaking of a mineral along its crystallographic planes, thus
reflecting crystal structure. CF:parting
b. The property or tendency of a rock to split along secondary, aligned
fractures or other closely spaced planes or textures, produced by
deformation or metamorphism. AGI
c. In quarrying, the cleavage of rocks is often called the rift.
Nelson
A compositional banding that is parallel to the cleavage rather than to
the bedding. It results from the mechanical movement of incompetent
material, such as argillaceous rocks, into the cleavage planes in a more
competent rock, such as sandstone. Ordinarily, the argillaceous bands are
only a few millimeters thick. See also:segregation banding
The plane along which cleavage takes place. Fay
As used by the diamond-cutting and diamond-bit-setting industries, the
more or less flat diamond fragments produced by splitting a crystalline
diamond along the octahedral plane. Such fragments are used primarily as a
material from which special-shaped, diamond-pointed cutting tools are
produced. See also:melee
To split a crystalline substance, such as a diamond, along a cleavage
plane. Long
A white, lamellar, or leaflike variety of albite, having an almost pure Ab
content and commonly forming fan-shaped aggregates of tabular crystals
that show mosaic development and appear as though bent; formed as a
late-stage mineral in pegmatites, replacing other minerals. Also spelled
clevelandite.
Splitting a crystal along a cleavage plane. Hess
Corn. A direction parallel to the bedding planes of a rock. CF:roughway;
quartering way. Fay
a. Scot. To load cages at the shaft bottom or at midworkings.
b. Scot. See:haulage clip
An abrupt chasm, cut, breach, or other sharp opening, such as a craggy
fissure in a rock, a wave-cut gully in a cliff, a trench on the ocean
bottom, a notch in the rim of a volcanic crater, or a narrow recess in a
cave floor. Obsolete syn: clift. AGI
A molecular mixture of thallium malonate and thallium formate. Used as a
heavy solution for the separation of minerals. The solution has a maximum
density of 4.25 g/cm3 at 20 degrees C. It is prepared by adding
formic acid to one of two equal quantities of thallium carbonate, and
adding malonic acid to the other until each is neutralized. The two
solutions are then mixed, filtered, and evaporated until almandite floats.
CF:Sonstadt solution; Klein solution; bromoform; methylene iodide.
Hess
A variety of uraninite containing a large percentage of UO3 ; also
rich in helium. Contains about 10% of the yttrium earths. Fay
a. In coal mining, a spring hook or snap hook used to attach the hoisting
rope to the bucket. Also called clivvy. Pryor, 3
b. A U-shaped iron hook used with an iron pin for connecting ropes to the
drawbars of cars or, when used with iron links, for coupling cars
together. Also used as a connecting link between chains or lines or to
hang a sheave in a drill tripod or derrick. Jones, 1; Long
a. A ferruginous bauxite from Cliache, Dalmatia, Croatia. English
b. Colloidal aluminum hydroxide occurring as one of the constituents of
bauxite. Also spelled kliachite. See also:laterite; sporogelite.
Syn:alumogel
a. Wales. Shale that is laminated, splitting easily along the planes of
deposition. Also called clift.
b. The strata of rocks above or between coal seams. Standard, 2