A claim, exclusive prospecting license, concession, right, or lease. A
grant under laws and mining regulations to a person or group of approved
persons of the right to develop and exploit a properly delineated area for
its mineral wealth. Pryor, 3
An instrument to facilitate observation of the essential elements of
visual tasks in coal mines. It is a brightness meter in which the
comparison field is illuminated by a cap lamp headpiece attached outside
the instrument. No internal electrical circuit exists other than that
which connects the photocell to the microammeter and the meter can
therefore be used anywhere in a safety-lamp mine without restrictions.
Roberts, 2
The act of digging under coal or in a soft strata in coal seams.
The minimum width necessary for the extraction of ore regardless of the
actual width of ore-bearing rock. See also:stoping width
The siftings of iron ore after calcination. Standard, 2
A tetragonal mineral, Pb3 O4 ; red; an alteration product of
galena or cerussite. Syn:red lead
A monoclinic mineral, (Fe,Mg)3 Si4 O10 (OH)2 ;
talc-pyrophyllite group; in the banded iron formations of Minnesota.
Syn:iron talc
a. Trace element or accessory element. See also:trace element
b. Less commonly, any of the elements present in the range of 0.1% to 1%,
between major elements in concentrations greater than 1% and trace
elements in concentrations less than 0.1%, or occasionally less than
0.01%.
In powder metallurgy, the portion of a powder sample that passes through a
standard sieve of specified number. Contrast with plus sieve.
ASM, 1
See:foresight
Stakes or points on the far side of the zero point from which a job was
originally laid out. Nichols, 1
A unit of angular measure equal to the 60th part of a degree and
containing 60 s of arc. Webster 3rd
An orthorhombic mineral, KAl2 (PO4 )2 (OH,F).4H (sub
2) O ; in phosphate rock in Western Australia and South Australia.
An epoch of the later Tertiary period, after the Oligocene and before the
Pliocene; also, the corresponding worldwide series of rocks. It is
considered to be a period when the Tertiary is designated as an era.
AGI
A monoclinic mineral, Na2 SO4 .10H2 O ; one perfect
cleavage; tastes cool, then saline and bitter; in evaporite deposits,
where it is mined as Glauber salt, and as an efflorescence.
Syn:Glauber salt
Mud.
See:muscovite
A violet-red breccia from Serravezza, Italy. Also known as African breccia
(breche Africaine).
A natural mixture of the rare-earth metals cerium, lanthanum, and
didymium; e.g., the waste matter from monazite sand after the extraction
of thoria may contain large quantities of ceria, lanthana, didymia,
yttria, and other substances. This is reduced to the metallic state by
converting the oxides to chlorides, and then recovering the metal by
electrolysis. The material obtained is an alloy containing about 50%
cerium and 45% lanthanum and didymium. Henderson
A monoclinic mineral, K2 SO4 .6KHSO4 (?) ; in silky
white fibers at Cape Miseno, Italy. (Not mizzonite.)