a. A term applied broadly in the Southwestern United States (esp. Arizona)
to a reddish-brown to buff or white calcareous material of secondary
accumulation; commonly found in layers on or near the surface of stony
soils of arid and semiarid regions, but also occurring as a subsoil
deposit in subhumid climates. It is composed largely of crusts of soluble
calcium salts in addition to such materials as gravel, sand, silt, and
clay. It is called hardpan, calcareous duricrust, or calcrete in some
localities, and kankar in parts of India. Syn:calcareous crust;
tepetate. ---Etymol: American Spanish, from a Spanish word for almost any
porous material (such as gravel) cemented by calcium carbonate.
AGI
b. Gravel, rock, soil, or alluvium cemented with soluble salts of sodium
in the nitrate deposits of the Atacama Desert of northern Chile and Peru;
it contains sodium nitrate (14% to 25%), potassium nitrate (2% to 3%),
sodium iodate (up to 1%) sodium chloride, sodium sulfate, and sodium
borate, mixed with brecciated clayey and sandy material in beds up to 2 m
thick. AGI
c. A term used in various geographic areas for a thin layer of clayey soil
capping a gold vein (Peru); whitish clay in the selvage of veins (Chile);
feldspar, white clay, or a compact transition limestone (Mexico); a
mineral vein recently discovered, or a bank composed of clay, sand, and
gravel in placer mining (Colombia). The term has been extended by some
authors to quartzite and kaolinite. AGI
Mex. Silver ore, generally colored with some iron sulfate, the result of
weathering. Hess
A local indicator plant for copper in Arizona, observed over the outcrop
of the San Manuel copper deposit. Here the distribution of this species is
confined to copper-rich soil, and its population density is closely
proportional to the copper content of the soil. Hawkes, 2
A device for sand dredging; the drag has a hinged afterbody that adjusts
to the angle of the drag arm, which may vary with the depth of water.
Scheffaur
A single-lift dredge with stacker. Buckets, which are closely spaced,
deliver to a trommel. The oversize is piled behind the dredge by a
conveyor (stacker). Undersize is washed on gold-saving tables on the deck;
tailings discharge astern through sluices.
a. A compact, massive, translucent to opaque variety of vesuvianite;
typically dark-green, olive-green, or grass-green, commonly mottled with
white or gray, closely resembling jade; an ornamental stone. Principal
sources are Fresno, Siskiyou, and Tulare Counties, CA.
Syn:American jade
b. A white variety of grossular garnet from Fresno County, CA.
a. An instrument used to measure precisely the thickness or diameter of
objects or the distance between two surfaces, etc. Long
b. An instrument used in conjunction with a microlog which, when lowered
down a borehole, measures and records the internal diameter throughout its
depth. BS, 9
c. An instrument consisting of a graduated beam and at right angles to it
a fixed arm and a movable arm which slides along the beam to measure the
diameter of logs and trees. Webster 3rd
Brake in which two brakeshoes are curved to the brake path and anchored
near the centerline of the drum. Sinclair, 5
A well log that shows the variations with depth in the diameter of an
uncased borehole. It is produced by spring-activated arms that measure the
varying widths of the hole as the device is drawn upward.
Syn:section-gage log
a. A heat-resistant alloy of aluminum, nickel, and iron. Hess
b. Iron or steel treated by calorizing. Hess
a. To drive tarred oakum into the seams between planks and fill with
pitch. Fay
b. Limestone or chalk; also spelled caulk. Arkell
c. A variety of barite. Hey, 1
d. To peen and draw metal toward and around a diamond being hand-wet in a
malleable-steel bit blank. Also called peen. Syn:peeler
e. To wick. Long
An orthorhombic mineral, (Ce,La)2 (CO3 )3 .4H2
O ; pale yellow; a source of rare-earth elements.
A monoclinic mineral, Cu2 Mg2 (CO3 )(OH)6 .2H
2 O ; azure-blue.
An apple- to emerald-green, massive, waxlike phosphate, possibly a mixture
of wavellite and turquoise.
Lanc. A shaly coal. Nelson
A rule stating that when a pillar has to be left in an inclined seam for
the support of a shaft or of a surface structure, a greater width should
be left on the rise side of the shaft or structure than on the dip side.
Briggs
A conical free-settling tank. Pulp is fed centrally; the finer solid
fraction overflows peripherally, and the coarser fraction is withdrawn at
a controlled rate via the apex at the cone's bottom.
See also:Caldecott cone; cone classifier. Pryor, 3
An early form of pneumatic flotation cell, still in limited use. Air is
blown in at the bottom of the tank at low pressure, through a porous
septum such as a blanket, and mineralized froth overflows along the sides
while the tailings progress to the discharge end. Pryor, 3
A continuous belt formed of fine screen wire travels horizontally between
two drums. Pulp, fed from above, flows through together with the finer
solids, while coarser material is discharged as the screen passes over the
end drum. Pryor, 3
A tetragonal mineral, 2[Hg2 Cl2 ] ; a secondary alteration
of mercury-bearing minerals. Syn:calomelite; calomelano;
horn quicksilver; mercurial horn ore.
See:calomel