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diamond-tooth saw

A circular saw for cutting stone with points of the teeth made of pieces
of diamonds. Mersereau, 2

diamond washer

An apparatus used for washing diamondiferous gravel.

diamond wheel

a. A grinding wheel in which crushed and sized industrial diamonds are
held in a resinoid, metal, or vitrified bond. ASM, 1
b. See:diamond saw

dianite

See:columbite

diaphaneity

a. The quality or state of being diaphanous. Specif., the ability of a
mineral to transmit light. CF:transparent; semitransparent; translucent;
opaque. Webster 3rd; Fay
b. Degrees of transparency of minerals. CF:transparent; translucent;
opaque.
c. See:transparency

diaphanous

Allowing light to show or to shine through. Webster 3rd

diaphorite

a. See:allagite
b. A monoclinic mineral, Pb2 Ag3 Sb3 S8 .

diaphragm

A porous or permeable membrane separating anode and cathode compartments
of an electrolytic cell from each other or from an intermediate
compartment. ASM, 1

diaphragm jig

In the gravity concentration of minerals, a jig with a flexible diaphragm
used to pulse water. The Bendelari, Pan-American, Denver, and Conset are
examples. Pryor, 1

diaphragm pump

A positive displacement pump used for lifting small quantities of water
and discharging them under low heads. It has a plunger arm operating
either on an eccentric shaft or a rocker arm thrusting on a rubber
diaphragm stretched over a cylinder. As the diaphragm is depressed, the
water and air in the cylinder are forced out through the discharge side of
the pump. As the diaphragm is lifted, a vacuum is created in the cylinder,
and water is forced in. Carson, 1

diaphragm-type washbox

A washbox in which the pulsating motion is produced by the reciprocating
movement of a diaphragm. BS, 5

diaphthoresis

See:retrograde metamorphism

diaphthorite

A crystalline rock in which minerals characteristic of a lower metamorphic
grade have developed by retrograde metamorphism at the expense of minerals
peculiar to a higher metamorphic grade. AGI

diapir

A dome or anticlinal fold in which the overlying rocks have been ruptured
by the squeezing-out of plastic core material. Diapirs in sedimentary
strata usually contain cores of salt or shale; igneous intrusions may also
show diapiric structure.

diapir fold

An anticline in which a mobile core, such as salt, has ruptured the more
brittle overlying rock. Syn:piercement dome; piercement fold.

diaschistic

Said of the rock of a minor intrusion that consists of a differentiate,
i.e., its composition is not the same as that of the parent magma.
CF:aschisite; aschistic. AGI

diaspore

An orthorhombic mineral, AlO(OH) ; white, colorless, or pale tints; in
bauxite and emery deposits; a source of aluminum. Formerly spelled
disaporite. Syn:kayserite

diaspore clay

A high-alumina refractory clay consisting essentially of the mineral
diaspore. It has been interpreted as a desilication product of associated
flint clay and other kaolinitic materials. Commercial diaspore of
first-grade quality contains more than 68% alumina.
See also:burley clay

diasporogelite

A colloidal form of aluminum hydroxide in bauxite. Syn:sporogelite;
cliachite. English

diastem

A relatively short interruption in sedimentation, involving only a brief
interval of time, with little or no erosion before deposition is resumed;
a paraconformity of very small time value. AGI

diasterism

Asterism seen by transmitted light. See also:asterism; epiasterism.