specific extraction of rock broken
Quantity of broken rock (ore) in volume or weight per foot drilled or
fired per quantity of explosive. Fraenkel
a. The ratio between the weight of a unit volume of a substance and that
of some other standard substance, under standard conditions of temperature
and pressure. For solids and liquids, the specific gravity is based upon
water as the standard. The true specific gravity of a body is based on the
volume of solid material, excluding all pores. The bulk or volume specific
gravity is based upon the volume as a whole--i.e., the solid material with
all included pores. The apparent specific gravity is based upon the volume
of the solid material plus the volume of the sealed pores.
See also:apparent specific gravity
b. Ratio of densities of a gas and air, based on dry air = 1.
Hartman, 2
c. The weight of a substance compared with the weight of an equal volume
of pure water at 4 degrees C. Specific gravity is numerically equal to
density given in grams per cubic centimeter or milliliter. CF:density
A hydrometer indicating the specific gravity or relation of the weight of
a given liquid per unit volume to the weight of a given unit volume of
water. See also:hydrometer; Marsh funnel. Long
specific gravity of soil grains
This is measured in a calibrated glass bottle with special precautions
against the inclusion of air. Such testing is applied in many soil problem
computations. See also:pycnometer
a. Heat required to raise the temperature of a unit weight of air 1
degrees F (0.56 degrees C). Usually, the specific heat at constant
pressure is used in air conditioning. For ordinary concrete and steel it
is 0.22 Btu/lb/ degrees F and 0.12 Btu/lb/ degrees F (0.92 kJ/kg/ degrees
C and 0.50 kJ/kg/ degrees C), respectively. Hartman, 2
b. The ratio of the amount of heat required to raise a unit weight of a
material 1 degree to the amount of heat required to raise the same unit
weight of water 1 degree. Brantly, 2
c. The heat in calories required to raise the temperature of 1 g of a
substance 1 degrees C. Webster 3rd
a. The mass of moisture per unit mass of dry air. Roberts, 1
b. Absolute humidity, or weight of water vapor contained per unit weight
of dry air. CF:relative humidity
Hartman, 1
Number of particles in unit volume of pulp. Pryor, 4
See:resistivity
The ratio of the volume of water that a given body of rock or soil will
hold against the pull of gravity to the volume of the body itself. It is
usually expressed as a percentage. CF:field capacity
a. A factor by which the performance of any particular design of impeller
for a centrifugal pump or water turbine can be computed. It is the speed
in revolutions per minute at which a geometrically similar impeller of
suitable diameter will rotate to deliver 1 gal/min (3.785 L/min) at 1 ft
(30.5 cm) head in the case of a pump. In a water turbine, the specific
speed is that at which a geometrically similar runner of suitable diameter
will turn to develop 1 hp (746 W) under a head of 1 ft (30.5 cm).
Hammond
b. The particular speed at which a fan achieves its maximum efficiency.
Roberts, 1
a. The surface area per unit of volume of soil particles. ASCE
b. The ratio of the total surface of a substance (as an adsorbent) to its
volume; surface area (as of a finely divided powder) per unit mass.
Webster 3rd
a. Volume of one gram at specified temperature. Pryor, 3
b. Volume per unit weight of dry air. Not equal to the reciprocal of
density, which is based on unit volume of mixture. Measured in cubic feet
per pound (cubic meters per kilogram). Hartman, 2
The dry weight per unit volume of the sediment in place.
See also:dry density
The ratio of the volume of water that a given mass of saturated rock or
soil will yield by gravity to the volume of that mass. This ratio is
stated as a percentage. CF:effective porosity
a. A sample, as of a fossil, rock, or ore. Among miners, it is often
restricted to selected or handsome samples, such as fine pieces of ore,
crystals, or fragments of quartz showing visible gold.
CF:hand specimen
b. A small mass of coal, rock, or, mineral, or soil, which gives, roughly,
an idea of the kind and quality of the deposit from which it was derived.
In the case of ore in particular, the specimen should admit of the
identification of the various minerals present. A specimen cannot be
viewed as a sample. Nelson
An employee whose duty is to watch carefully, in all parts of the mine,
for the appearance of high-grade mineral, and when it is likely that such
spots will be opened up, should be the first person at the face after the
blast to prevent high-grading (the theft of valuable samples).
Hoover
Another name for high-grading. Hoover
In mineral dressing, unusually rich pieces of ore or characteristic
constituents thereof in coarsely crystalline form--not representative
samples. Pryor, 4
A small piece of alluvial gold weighing up to 1 oz or 2 oz (28 g or 56 g).
Gordon
An early name for talc or steatite. Etymol: German "Speckstein", "bacon
stone," alluding to its greasy feel.