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order of crystallization

The apparent chronological sequence in which crystallization of the
various minerals of an assemblage takes place, as evidenced mainly by
textural features. See also:paragenesis

order of persistence

See:stability series

order of reaction

A classification of chemical reactions based on the index of the power to
which concentration terms are raised in the expression for the
instantaneous velocity of the reaction; i.e., on the apparent number of
molecules which interact. CTD

ordinary kriging

A variety of kriging which assumes that local means are not necessarily
closely related to the population mean, and which therefore uses only the
samples in the local neighborhood for the estimate. Ordinary kriging is
the most commonly used method for environmental situations.
See also:kriging

ordinary ray

a. In a uniaxial crystal, that ray that travels with constant velocity in
any direction within it. Anderson
b. In mineral optics, a light ray that, because of its crystallographic
orientation, follows Snell's law, n=sini/sinr, where n is the refractive
index, i is the angle of incidence, and r is the angle of refraction. In
anisotropic crystals, not all light rays follow Snell's law and are,
hence, "extraordinary rays." CF:law of refraction

ordinate

Y-axis; the vertical scale of a graph.

ordnance bench mark

Survey station the level of which has been officially fixed with reference
to the ordnance datum, the arbitrary mean sea level at Newlyn in Cornwall,
England. Pryor, 3

ordnance survey

Originally, a military mapping activity; now a precise survey maintained
by government which maps land and building features of Great Britain in
close detail. Pryor, 3

ordonezite

A tetragonal mineral, ZnSb2 O6 ; brown.

ore

a. The naturally occurring material from which a mineral or minerals of
economic value can be extracted profitably or to satisfy social or
political objectives. The term is generally but not always used to refer
to metalliferous material, and is often modified by the names of the
valuable constituent; e.g., iron ore. See also:mineral; mineral deposit;
ore mineral. Syn:orebody
b. The term ores is sometimes applied collectively to opaque accessory
minerals, such as ilmenite and magnetite, in igneous rocks. AGI

ore band

Zone of rock rich in ore.

ore-bearing fluid

See:hydrothermal solution

ore bed

a. Metal-rich layer in a sequence of sedimentary rocks. AGI
b. Economic aggregation of minerals occurring between or in rocks of
sedimentary origin.

ore bin

a. A receptacle for ore awaiting treatment or shipment. Fay
b. Robustly constructed steel, wooden, or concrete structure which
receives intermittent supplies of mined ore and can transfer them
continuously by rate-controlled withdrawal systems (bottom gates and ore
feeders) to the treatment plant. Thus a buffer stock is held which allows
a mine to hoist ore intermittently without bringing milling operations to
a standstill. It characteristically receives a weighed-in input of finely
broken ore from the final dry-crushing section (usually between 1-in and
3/8-in (2.54-cm and 9.5-mm) maximum particle size). The surge bin is a
much smaller one, able to receive a dumped load of run-of-mine ore and to
transfer it at a regular rate to the crushing system between arrivals of
further skip loads. Pryor, 3

ore blending

Method whereby a mine, or a group of mines, served by a common mill, sends
ores of slightly varied character for treatment and separate bins or
stockpiles are provided. From these, regulated percentages of ores are
drawn and blended to provide a steady and predictable feed to the mineral
dressing plant. Pryor, 3

ore block

A section of an orebody, usually rectangular, that is used for estimates
of overall tonnage and quality. See also:blocking out

ore blocked out

See:developed reserve

ore boat

A boat constructed esp. for transporting iron ore on the Great Lakes.
Mersereau, 2

orebody

A continuous, well-defined mass of material of sufficient ore content to
make extraction economically feasible. See also:ore; mineral deposit.
AGI

ore boil

A reaction that occurs in an open-hearth furnace in which the carbon
monoxide released by the oxidation of carbon causes a violent agitation of
the metal as it escapes. Newton, 1

ore bridge

A large electric gantry-type crane which, by means of a clamshell bucket,
stocks ore or carries it from a stockpile into bins or a larry car on a
trestle. Fay