A circular or octagonal shaft furnace, maintaining or increasing its
diameter toward the top, and having several tuyeres; used in smelting lead
ores. Fay
A massive or earthy, apple-green, nickel-bearing phyllosilicate; probably
willemseite or kerolite having disordered stacking; (Ni,Mg)6 Si
8 O20 (OH)4 .
Crude copper matte of about 78% copper, obtained from the smelting of
sulfide copper ores. Bennett
See:wedge rock
An open crystal form consisting of two parallel faces. AGI
a. A marked thinning or squeezing of a rock layer; e.g., a coming-together
of the walls of a vein, or of the roof and floor of a coal seam, so that
the ore or coal is more or less completely displaced. See also:nip
CF:make; want. Standard, 2
b. A thin place or a narrow part of, an orebody; the part of a mineral
zone that almost disappears before it widens out in another place to form
an extensive orebody. AGI
c. The binding action caused when drillhole walls close in before casing
is emplaced, resulting from failure of soft or plastic formations.
Long
A kind of crowbar with a short projection and a heel or fulcrum at the
end; a pinch. Used to pry forward heavy objects. Standard, 2
Where a vein narrows, as if the walls had been squeezed in. Where the
walls meet, the vein is said to be pinched out. See also:pinching out;
pinch.
Where a lode or stratum narrows down and disappears. See also:pinch
BCI
To taper or narrow progressively to extinction; to thin out. AGI
A revolving table on which are tapering spiral copper cleats on a linoleum
cover. The tailings are washed over the riffles and off the edge, while
the concentrates are delivered at the end of the riffles. Liddell
a. A cast roller, designed to keep the haulage rope centered between rail
tracks. Spiral grooves on the sides return a straying rope to the central
grooves. Works in one direction only. Pryor, 3
b. See:line oiler
Very viscous; dark brown to black; liquid or semisolid; strong
characteristic odor; sharp taste; translucent in thin layers; hardens with
aging; sp gr, 1.03 to 1.07; boiling point, ranges from 240 to 400 degrees
C; soluble in alcohol, ether, chloroform, acetone, glacial acetic acid,
fixed and volatile oils, and sodium hydroxide; and insoluble in water.
Chief constituents are complex phenols; also present are turpentine,
rosin, toluene, xylene, and other hydrocarbons. Used in flotation.
CCD, 2
An acoustic pulse signal projected by an echo-ranging transducer.
Hy
A former name for nontronite. See also:nontronite
Smaller of a pair of toothed wheels, e.g., the pinion geared to the driven
crown wheel of a ball mill. Pryor, 3
A drive gear that is smaller than the gear it turns. Nichols, 1
A compact, fine-grained, generally impure mica near muscovite in
composition; dull-gray, green, or brown; derived from the alteration of
other minerals, esp. cordierite, nepheline, scapolite, spodumene, and
feldspar.
a. Any high tower or spire-shaped pillar of rock, alone or cresting a
summit. A tall, slender, pointed mass; esp., a lofty peak. AGI
b. A sharp pyramid or cone-shaped rock under water or showing above it.
AGI
c. In alluvial mining, a spine or pillar in limestone bedrock of an
irregular and serrated type, in which it is difficult for dredge buckets
to work. Pryor, 3
A drill-rod coupling that has been permanently attached to the body of the
rod by a metal dowel (or pin) driven into a small hole drilled at the
point in the rod where the coupling is screwed into the body of the rod.
Long
a. Boulder clay, from Cumberland, Northumberland, and Lancashire, England,
and North Wales. Arkell
b. Coarse gravel or sandstone conglomerate. Arkell