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star facet

Small triangular facet situated between the bezel facets and the table on
the crown of an American (Tolkowski theoretical) brilliant-cut diamond.

star feeder

A rotating feeder consisting of a horizontal shaft fitted with radial
blades running within a close-fitting cylindrical chamber provided with an
inlet and an outlet. Also called star gate; star valve (undesirable
usage). BS, 5

star garnet

Variant of almandine. Hey, 1

starkeyite

A monoclinic mineral, MgSO4 .4H2 O ; rozenite group. Named
for the Starkey Mine, Madison County, MO. Syn:leonhardtite

Starlite

Trade name given by Kunz to artificially-colored blue zircon from
Thailand. English

star metal

See:star antimony

star quartz

A variety of quartz containing within the crystal whitish or colored
starlike radiations along the diametral planes. The asterism is due to the
inclusion of submicroscopic needles of another mineral arranged in
parallel fashion. In star blue quartz in Virginia and Texas, the other
mineral is rutile. See also:asteriated quartz

star reamer

A star-shaped tool for regulating the diameter of, or straightening, a
borehole.

star ruby

A semiopaque to semitransparent asteriated variety of ruby normally having
six chatoyant rays. CF:corundum cat's eye

star sapphire

A semiopaque to semitransparent asteriated variety of sapphire normally
with six rays resulting from the presence of microscopic crystals (e.g.,
rutile needles) in various orientations with the gemstone.
See also:asteria

star stone

a. An asteria; esp. a star sapphire. AGI
b. Less correctly, any asteriated stone, including even petrified wood
containing small starlike figures in its more transparent parts.
AGI

starter

a. A slightly larger drill used for making the beginning of a hole, the
remainder of the hole being made with a drill of smaller gage known as a
follower. Fay
b. Pennsylvania. The miner who ascends to the battery to start the coal to
run. See also:battery starter
c. Protective equipment to ensure that an electric motor does not receive
too high a current when starting. Hammond

starter bar

A steel reinforcing bar embedded in the concrete and projecting through a
construction joint to bind adjoining masses of concrete together.
Hammond

starting barrel

A short core barrel used to begin coring operations when the distance
between the drill chuck and the bottom of the hole, or to the rock surface
in which a borehole is to be collared, is too short to permit use of a
full 1.5-m-long or 3-m-long core barrel. Long

starting casing barrel

A short piece of casing to which a casing bit and shell are attached and
used under the same conditions as a starting barrel.
See also:starting barrel

starting sheet

A thin sheet of metal used as the cathode in electrolytic refining.
ASM, 1

starting submergence

In an air lift, the distance below the static head at which the air picks
up water. Lewis

starvation

a. In comminution, avoidance of crowding in the machine by restricting
rate of feed.
b. In conditioning for flotation, use of threshold quantity of collector
agent to aid in selective adsorption by the desired species of mineral.

Stassfurt deposits

A series of saline minerals, found in the Triassic rocks at Stassfurt,
Saxony, Germany, which include halite, anhydrite, kieserite, gypsum, and
boracite.

stassfurtite

A massive variety of boracite found in Germany. It resembles a
fine-grained white marble; sometimes has a subcolumnar structure.
Fay; CTD

statement of performance

A statement describing the scope and duty of a plant in terms, e.g., of
the tonnage of coal treated per hour, the processes used, the separations
effected and sizes produced; sometimes also used to express the results of
plant operation. BS, 5