A method of cupellation using a large reverberatory furnace with a fixed
bed and a movable roof. The bullion to be cupelled is all charged at once,
and the silver is not refined in the same furnace where the cupellation is
carried on. Fay
See:pyramid cut
Archaic name for amber.
An isometric mineral, Cu26 Fe4 Ge4 S32 ;
associated with tennantite, sphalerite, enargite, pyrite, and bornite; at
the Tsumeb Mine in Namibia.
A grayish-white, metallic element occurring in argyrodite, a sulfide of
germanium and silver; and in germanite, zinc ores, and coal. Its presence
in coal ensures a large reserve of the element in the future. Symbol, Ge.
It is a very important semiconductor material. Also used as an alloying
agent, a phosphor, a catalyst, and for infrared detectors and optical
equipment. Handbook of Chemistry and Physics, 3
GeO2 ; melting point, 1,115 degrees C. This oxide is a glass former
and provides some unique properties; e.g., greater dispersion, lower
melting temperature, and higher transmissivity for infrared radiation.
Some germanium oxide complexes and solid solutions have ferroelectric
properties. Colorless; sp gr, 4.228 (at 25 degrees C); hexagonal; soluble
in alkalies; and slightly soluble in acids and in water. Used as an
ingredient of special glass mixtures.
Lee; CCD, 2; Handbook of Chemistry and Physics, 2
Ge3 N4 ; decomposes at 800 degrees C. A special
electroceramic of high resistivity. Dodd
See:false lapis
This process consists in (1) roasting copper ore, (2) melting and
obtaining a matte with 30% to 40% copper called coarse metal, (3) roasting
the coarse metal, (4) melting and obtaining a matte with 60% to 70% copper
called fine metal, (5) roasting the fine metal, and (6) melting and
obtaining black copper. Fay
A metal made from charcoal iron obtained from bog iron or from sparry
carbonate of iron. Fay
An isometric mineral, NiAsS ; cobaltite group; massive; sp gr, 5.9 to 6.0;
in sulfide veins intergrown with maucherite, nickeline, and chalcopyrite
at the Garson and Falconbridge Mines, Sudbury, ON, Can.; with cobaltite
and rammelsbergite in the silver-arsenide ores of Cobalt, ON, Can.; a
source of nickel.
A shaft furnace, filled with terraces or shelves, through which crushed
ore is caused to fall for roasting. Fay
A monoclinic mineral, Na2 (Sb,As)8 S13 .2H2 O;
dark red; soft; in fine granular aggregates, groups of small plates, or
spherules in clay, with borates at the Baker Mine, Kramer district, Kern
County, CA.
Arkansas. To have an opportunity to load out all the coal a miner has
loosened. Fay
Substance used to combine with the residual oxygen in an electric bulb or
tube. Its use is called gettering. Pryor, 3
The actual process of digging clay, by hand or by excavator; getting and
transporting form the successive stages of winning. Dodd
An isometric mineral, Pt(Sb,Bi)2 ; pyrite group; forms tiny grains
intergrown with native platinum in concentrates at the Dreikop Mine,
eastern Transvaal, Republic of South Africa.
See:loellingite
A valley or other area that contains numerous springs, geysers, and
steaming fissures fed by the same ground-water flow. AGI
Syn:siliceous sinter
scaly, or filamentous incrustation of opaline silica deposited by
precipitation from the waters of a geyser. AGI
See:phantom crystal