A triclinic mineral, CuFe6 (PO4 )4 (OH)8 .4H
2 O ; turquoise group; occurs in sheaflike crystalline
incrustations; forms a series with turquoise.
See:chalcocite
A lead-gray copper-antimony sulfide, CuSbS2 . Also called
wolfsbergite. Syn:rosite; antimonial copper. Fay
A capillary variety of cuprite in fine, slender interlacing fibrous
crystals. Syn:cuprite; plush copper ore; hair copper.
A soft, earthy, fine-textured, usually white to light-gray or buff
limestone of marine origin. It consists almost wholly (90% to 99%) of
calcite, formed mainly by shallow-water accumulation of calcareous remains
of floating microorganisms (chiefly foraminifers) and of comminuted
remains of calcareous algae, set in a structureless matrix of very finely
crystalline calcite. The rock is porous, somewhat friable, and only
slightly coherent. AGI
Any soft, milky-colored rock resembling white chalk, such as talc,
calcareous tufa, diatomaceous shale, volcanic tuff, or white limestone.
AGI
A commonly dull or earthy, soft to hard, sometimes finely porous chert of
essentially uniform composition, having an uneven or rough fracture
surface, and resembling chalk. Syn:dead chert
Obsolete syn: cotton chert. CF:granular chert
Ore feeder used with stamp batteries to regulate the rate of entry of ore
to a mortar box. A horizontal plate is turned by linkages operated when
the central stamp falls below a prefixed point; it then draws ore from
feeding bin. Pryor, 3
A former name for cubanite.
See:siderite
a. A miner's working place, sometimes referred to as a room or breast.
Hudson
b. A large irregular or rounded body of ore, occurring alone or as an
expansion of a vein.
c. A body of ore with definite boundaries, apparently filling a
preexisting cavern.
d. A powder-storage room in a mine.
e. To enlarge the bottom of a drill hole by the use of explosives, so that
a sufficient blasting charge may be loaded for the final shot.
Syn:spring
f. A space or gallery excavated in a quarry or underground mine to receive
a large explosive charge. See also:heading blast
A modification of sublevel stoping by which a series of sublevels are
successively caved. See also:sublevel stoping
A large-scale blast in which explosives in bulk are placed in excavated
subterranean chambers. Also called coyote blast; gopher-hole blast.
Webster 2nd
A portion of the wall of a lode that is fissured and filled with ore.
See also:chamber
a. A vein in which the walls, particularly the hanging wall, are irregular
and brecciated, owing to the formation of the vein under low pressure at
shallow depth. See also:chambered lode
b. Stockwork.
a. The process of enlarging a portion of a blast hole (usually the bottom)
by firing a series of small explosive charges. It can also be done by
mechanical or thermal methods.
b. The enlarging of the bottom of a quarry blasting hole by the repeated
firing of small explosive charges. The enlarged hole or chamber is then
loaded with the proper explosive charge, stemmed, and fired to break down
the quarry face. See also:concentrated charge
c. A borehole in which portions of the sidewalls are breaking away and
forming cavities or small chambers. Long
An orthorhombic mineral, Mn3 B7 O13 Cl ; the
manganese analogue of boracite; occurs in brines.
See:sublevel stoping
A rare variety of tourmaline, olive green in daylight, changing to
brownish-red in most artificial light. Syn:alexandritelike tourmaline
To bevel or slope an edge or corner. Also spelled chanfer.