An artificially prepared clay mineral with calcium in place of magnesium.
Spencer, 2
See:apatite
See:anorthite
See:autunite
a. Conglomerate consisting of surficial sand and gravel cemented into a
hard mass by calcium carbonate precipitated from solution and redeposited
through the agency of infiltrating waters, or deposited by the escape of
carbon dioxide from vadose water. AGI
b. A calcareous duricrust; caliche. Etymol: "cal"careous + con"crete."
CF:silcrete; ferricrete. AGI
A deposit composed of sapropel (dominant) and remains of calcareous algae.
Tomkeieff
A metamorphosed argillaceous limestone with a schistose structure produced
by parallelism of platy minerals. AGI
A fine-grained metamorphic rock containing a high percentage of
calc-silicate minerals. See also:calc-flinta; hornfels; limurite; skarn;
tactite.
A marble in which calcium silicate and/or magnesium silicate minerals are
conspicuous. Syn:calciphyre
A metamorphic rock consisting mainly of calcium-bearing silicates, such as
diopside and wollastonite, and formed by metamorphism of impure limestone
or dolomite; associated with skarn-type mineral deposits.
Syn:lime-silicate rock
See:travertine
Coarsely crystalline calcite. Also spelled: calc-spar.
See also:calcite
See:tufa
A secondary mineral, Ca(UO2 )3 (MoO4 )3 (OH)
2 .11H2 O .
A conical tank used to settle and discharge as a continuous underflow the
relatively coarse sand from an overflowing stream of mineral pulp.
See also:cone classifier; Callow cone. Pryor, 3
A large, basin-shaped volcanic depression, more or less circular, the
diameter of which is many times greater than that of the included vent or
vents, no matter what the steepness of the walls or the form of the floor
may be. CF:crater
An isometric mineral, (Mn,Ca)(Fe,Al)2 (SiO4 )3 ; the
dark reddish-brown manganese-iron end member of the garnet group.
See:bell mold; caldron bottom; kettle bottom.
a. Mud-filled prostrate trunk of sigillaria in the roof of certain coal
seams. The trunk is a separate mass of rock, with a film of coal around
it. It is liable to collapse without any warning sound. Also called
horseback. Syn:caldron; kettle bottom. See also:pot
b. Eng. A cone-shaped mass with slippery surfaces found in the roof of
some seams. It sometimes comprises a ring of coal around a core of
material differing slightly from the ordinary roof. CF:pot bottom
called pothole. SMRB
An orthorhombic mineral, Pb5 Cu2 (CO3 )(SO4 )
3 (OH)6 ; green (not to be confused with celadonite).
The churn-drill winch used for handling casing and for odd jobs. Also
called casing reel. Nichols, 1