Alteration of rocks or minerals by the reaction of hydrothermal water with
preexisting solid phases. AGI
A mineral deposit that originated from hot, ascending aqueous solutions
derived from a magma. CF:hypothermal deposit
A hot-water solution originating within the Earth and carrying dissolved
mineral substances. Syn:ore-bearing fluid; ore-forming fluid.
AGI
That stage in the cooling of a magma during which the residual fluid is
strongly enriched in water and other volatiles. The exact limits of the
stage are variously defined by different authors, in terms of phase
assemblage, temperature, composition, and/or vapor pressure; most
definitions consider it as the last stage of igneous activity, coming at a
later time, and hence at a lower temperature, than the pegmatitic stage.
AGI
Mineral synthesis in the presence of water at elevated temperatures.
AGI
a. Containing water; watery; specif., hydrated. Webster 3rd
b. Minerals that contain water chemically combined. Gordon
Salts containing water of crystallization.
A permitted device, used in some English coal mines, that resembles Cardox
in that a steel cylinder with a thin shearing disk is used. However, the
charge is not liquid carbon dioxide but rather a powder composed chiefly
of ammonium chloride and sodium nitrate. It is proportioned to give water,
nitrogen, and salt as the products of combustion. On being ignited, this
powder is gasified and shears the steel disk, with the gas escaping into
the hole. Lewis
An alternative to explosives for breaking down coal in safety lamp mines.
The gasification of the Hydrox charge generates sufficient pressure within
the shothole to break down the coal. The original plastic disc attached to
the charge has been replaced by a metal disc separately seated. The
gaseous products from the Hydrox charge are mainly carbon dioxide,
nitrogen, and water vapor. The tubes can be recharged underground. The
method gives a high yield of +2 in (5.1 cm) in size of coal.
Nelson
See:phenol
OH; the characteristic radical of bases, consisting of one atom of
hydrogen and one atom of oxygen. The valence of this radical or anion is
-1. Crispin
A hexagonal mineral, Ca5 (PO4 )3 (OH) ; apatite
group; an uncommon apatite in which hydroxyl predominates over fluorine
and chlorine. Formerly spelled hydroxyapatite.
A monoclinic mineral, 2[Zn5 (CO3 )2 (OH)6 ] ;
forms massive, fibrous, earthy, or compact encrustations with blue
luminescence; a secondary mineral in weathered zones of zinc deposits
commonly associated with smithsonite or sphalerite; a source of zinc.
Syn:zinc bloom
See:rain gage
Any of several instruments for measuring the humidity of the atmosphere.
See also:psychrometer
Measurement of atmospheric humidity.
The water content of an air-dried soil. ASCE
A device sensitive to humidity changes and arranged to actuate other
equipments when a predetermined humidity is attained. Syn:humidostat
Strock, 2
Pertaining to an igneous intrusion, or to the rock of that intrusion,
whose depth is intermediate between that of abyssal or plutonic and the
surface. This distinction is not considered relevant by some petrologists.
CF:abyssal; plutonic. Syn:subvolcanic
An igneous rock that has risen from the depths as magma but solidified
mainly as such minor intrusions as dikes and sills.
A prefix from the Greek meaning over, above, or abnormally great.