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crucible steel

Steel made by melting blister bar, wrought iron, charcoal, and ferroalloys
in crucibles that hold about 100 lb (45 kg). This was the first process to
produce steel in a molten condition, hence the product called cast steel.
Mainly used for the manufacture of tool steels, but now largely replaced
by the electric-furnace process. CTD

crucible swelling number

The number that defines, by reference to a series of standard profiles,
the size and shape of the residue produced when a standard weight of coal
is heated under standard conditions. BS, 1

cruciform bit

a. See:cross-chopping bit
b. Percussive rock drill bit having four chisel-shaped cutting edges in
the form of a cross on the face of the bit. Also called cross bit.
Long

crucite

a. See:chiastolite; cross-stone.
b. Pseudomorph of hematite or limonite after arsenopyrite.

crud

A solid-stabilized emulsion that tends to collect at the agueous/organic
interface in the settler of a solvent extraction circuit. Kordosky

crude

A substance in its natural unprocessed state. Crude ore or crude oil, for
example. In a natural state; not cooked or prepared by fire or heat; not
altered or prepared for use by any process; not refined. Syn. for raw;
crude oil. Webster 3rd

crude anthracene

Solid product containing anthracene. Obtained on cooling the coal-tar
distillate collected above 270 degrees C. Bennett

crude asbestos

Hand selected cross-vein material of longest fibres in native or
unfiberized form. It comes in chunks and must be mechanically processed to
develop the usefulness of the fibre. Arbiter

crude mica

The crude crystals or books as extracted from the mine. Skow

crude ore

The unconcentrated ore as it leaves the mine.

crude-ore bin

A bin in which ore is dumped as it comes from the mine.

crude sulfur

Elemental sulfur that is 99.0% to 99.9% pure and is free from arsenic,
selenium, and tellurium. USBM, 7

crudy asbestos

Refers to asbestos that has been only partially milled, so that the fiber
has not been fluffed but only separated from the rock. Most of the
asbestos is still in the form of bundles of fibers like spicules.
AIME, 1

crump

Ground movement, perhaps violent, due to failure under stress of ground
surrounding underground workings usually in coal, so named because of
sound produced. See also:bump

crush

a. A species of fault in coal. Fay
b. Breakage of supports of underground workings under roof pressure.
Pryor, 3

crushability

The relative ease of crushing a sample under standard conditions.
BS, 5

crush belt

A belt of intensely crushed rock.

crush border

A microscopic, granular metamorphic structure sometimes characterizing
adjacent feldspar particles in granite due to their having been crushed
together during or subsequent to crystallization. AGI

crush breccia

A breccia formed essentially in situ by cataclasis, esp. along a fault.
See also:cataclasite; crush conglomerate. CF:tectonic breccia

crush bursts

Rockbursts in which there is actual failure at the face accompanied by
movement of the walls. Higham

crush conglomerate

a. A conglomerate produced by the crushing of rock strata in the shearing
often accompanying folding. Standard, 2
b. Similar to a fault breccia, except the fragments are more rounded in a
crush conglomerate. AGI
c. See:tectonic conglomerate; pseudoconglomerate; crush breccia.