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pisolite

a. A sedimentary rock, usually a limestone, made up chiefly of pisoliths
cemented together; a coarse-grained oolite. Syn:peastone
b. A term often used for a pisolith, or one of the spherical particles of
a pisolite.---Etymol: Greek pisos, pea. CF:oolite
c. An individual unit in a mass of accretionary lapilli. AGI

pisolith

One of the small, round or ellipsoidal accretionary bodies in a
sedimentary rock, resembling a pea in size and shape, and constituting one
of the grains that make up a pisolite. It is often formed of calcium
carbonate, and some are thought to have been produced by a biochemical
algal-encrustation process. A pisolith is larger and less regular in form
than an oolith, although it has the same concentric and radial internal
structure. The term is sometimes used to refer to the rock made up of
pisoliths. CF:oolith

pisolitic tuff

An indurated pyroclastic deposit composed chiefly of accretionary lapilli
or pisolites. AGI

pistacite

A pistachio-green ferric-iron-rich variety of epidote. Also spelled
pistazite.

pistol pipe

In metalworking, the tuyere of a hot-blast furnace. Fay

piston

The working part of a pump, hydraulic cylinder, or engine that moves back
and forth in the cylinder; it is generally equipped with one or several
rings or cups to control the passage of fluid. It ejects the fluid from
the cylinder, as in a pump, or receives force from the fluid, which causes
a reciprocating motion, as in an engine. Long

piston corer

An oceanographic corer containing a piston inside the cylinder which
reduces friction by creating suction. There are several varieties,
including the Ewing corer, the Mackereth sampler, and the Kullenberg
corer. CF:gravity corer

piston drive-sampler

See:piston sampler

piston sampler

A drive sampler equipped with either a free or a retractable-type piston
that retreats up into the barrel of the sampler in contact with the top of
the soil sample as the sampler is pressed into the formation being
sampled. CF:drive sampler

piston speed

Total feet or meters of travel of a piston in 1 min. Nichols, 1

piston-type sampler

See:piston sampler

piston-type washbox

See:plunger-type washbox

pit

a. Depression produced in a metal surface by nonuniform electrodeposition
or by corrsion. Lowenheim
b. Excavation to hold quantities of water and drilling fluids.
Wheeler, R.R.
c. So. Wales. Long, open-air fire for converting coal into coke for
blast-furnace purposes. Fay
d. A mine, quarry, or excavation worked by the open-cut method to obtain
material of value.
e. The shaft of a mine; a shaft mine; a trial pit. Nelson
f. The underground portion of a colliery, including all workings. Used in
many combinations, as pit car, pit clothes, etc.
g. In hydraulic mining, the excavation in which piping is carried forward.
h. Commonly, a coal mine, but not usually called so by workers, except in
reference to surface mining where the workings may be known as a strip
pit. BCI
i. See:abyss

pit ash

Ash in coal derived from the dirt bands, adjoining shales or cleat
minerals. Tomkeieff

pit bank

a. Eng. The raised ground or platforms upon which the coal is sorted and
screened at the surface. See also:heapstead; pit brow; pithead;
pit hill.
b. Scot. The surface of the ground at the mouth of a pit, or shaft.

pit bar

One of the wooden props bracing the sides of a pit. Standard, 2

pit boss

A mine foreman who is in direct charge of workers in a specific portion of
a pit or mine. Also called shift boss. See also:pit foreman
DOT

pit bottom

The bottom of a shaft and all the equipment and roadways around it.
See also:loop-type pit bottom

pit brow

The pithead, and in particular, the mouth of the shaft. The edge or brow
of a pit. See also:brow

pit cage

The structure used in mine shafts for transport purposes.
See also:cage

pit-car loader

A short, electrically powered, lightweight elevating conveyor designed for
use in working places, to facilitate the loading of large cars or to aid
in shoveling long distances. The loader shovels into the hopper end and
the conveyor carries the coal to the car. Jones, 1