An etchant for iron or steel, consisting of a solution of 10% to 20%
ammonium persulfate in water. Osborne
A method of growing single crystals of refractory oxides, and of other
compounds, by pulling from the pure melt; the compound must melt
congruently. Dodd
A monoclinic mineral, (Ca,Na2 ,K2 )5 Al10 Si
38 O96 .25H2 O ; zeolite group; in a pegmatite at San
Piero, Elba, Italy.
A fine-grained extrusive rock with the same general composition as
andesite, but having a less calcic plagioclase and more quartz; according
to many, it is the extrusive equivalent of granodiorite.
Syn:quartz andesite
ancient Roman province of Dacia (now part of Romania). AGI
Eng. Insufficient ventilation of a mine; dead air.
A term applied to a rock texture produced by a symplectic intergrowth, in
which one mineral is penetrated by fingerlike projections from another
mineral; also, said of a rock exhibiting such texture.
See also:dactylotype intergrowth; symplectic. AGI
A textural term applied by Shand in 1906 to the intergrowth of sodalite
with orthoclase in borolanite and its associates. The sodalite is altered
to pinitic mica and appears in threadlike or vermicular aggregates closely
packed in a matrix of orthoclase. Holmes, 2
a. A mineral intergrowth in which thin successive layers resemble a
fingerprint pattern, as in some orthoclase-nepheline intergrowths.
Hess
b. A symplectic intergrowth in which fingerlike projections of one mineral
penetrate another. See also:dactylitic
N. of Eng. In coal mining, to mix (combustible gases) with atmospheric air
to such an extent that the mixture is incapable of exploding. Also called
dash. See also:dashing
The circulation, control, and utilization of air produced by the fan to
ventilate the mine workings. See also:circulation of air
Nelson
An early type of universal rolling mill provided with both vertical and
horizontal rolls so that a part could be rolled on all sides in one
operation. Osborne
An etchant used to distinguish carbides in chromium steels and tungstides
in high-speed steels. The solution contains 20 g of potassium ferricyanide
and 10 g of potassium hydroxide in 100 mL of water. Osborne
A resinous, yellowish-white carbonate-apatite mineral or association
sometimes occurring as concretionary spherulites. Now called
carbonate-hydroxylapatite. AGI
Classification through the hydrocyclone. Pryor, 3
See:schroeckingerite
a. The rapids in a deep, narrow stream confined between the rock walls of
a canyon or gorge; e.g., The Dalles of the Columbia River where it flows
over columnar basalt. AGI
b. A steep-sided part of a stream channel, near the dalles proper, marked
by clefts, ravines, or gorges; e.g., along the Wisconsin River,
WI.---Etymol: French plural of dalle, gutter. Syn:dells
In a mixture of gases, the total pressure is equal to the sum of the
pressures that the gases would exert separately.
See also:partial pressure
A triclinic mineral, K2 ZrSi6 O15 ; at Ascension
Island in the Atlantic Ocean.
a. A barrier to keep foul air or water, from mine workings.
See also:stopping; bulkhead. Fay
b. An airtight barrier to isolate underground workings that are on fire.
CTD
c. The wall of refractory material, forming the front of the forehearth of
a blast furnace, that is built on the inside of a supporting iron plate
(dam plate). Iron is tapped through a hole in the dam, and cinder through
a notch in the top of the dam. See also:Lurmann front
See:contragradation
A hypabyssal rock composed of phenocrysts of biotite and titanaugite in a
fine-grained groundmass of pyroxene, biotite, perovskite, and magnetite,
with interstitial nepheline, microcline, and calcite. The name, given by
Broegger in 1921, is for the locality Damkjern (or Damtjern), Fen complex,
Norway. Also spelled: damtjernite. AGI