A glossary of mining and metallurgical terms

94 A GLOSSARY OF MINING AND METALLURGICAL TERMS.
Wood-tin. Tinstone of light wood-color.
Wootz. See Steel.
Work. Ore not yet dressed.
Working. See Labor. The Spanish and the English term are
synonyiuous in meaning and alike in application. A working may
be a shaft, quarry, level, open-cut, or stope, etc.
Working-barrel, CoRN. The cylinder in which a pump piston
works.
Working home. Working toward the main shaft in extracting ore
or coal, as in long wall retreating.
Working-out. Working away from the main shaft in extracting
ore or coal, as in longirall advancing.
Work-lead. See Base bullion.
Yellow-ore. Corn. Chalcopyrite. See Copper o'res.
Yokings. See Stoivces.
Zaicn, Corn. A cavern.
Ziervogel process. The extraction of silver from sulphuret ores or
matte by roasting in such a way as to form sulphate of silver,
leaching this out with hot water, and precipitating the silver by
means of metallic copper.
Zighyr, zigger, or sicker, Corn. To percolate, trickle or ooze, as
water through a crack. From the Germ., sickern.
Zinc-dust. Finely-divided zinc, zinc-oxide, and impurities, inci-
dentally produced in the manufacture of spelter. It is sometimes
used as an inferior paint {zinc-gray).
Zinc-gray. See Zinc-dust.
Zinc-ores. Red 07'e{zincite, oxide) ; black-jack {zinc-blende, sphal-
erite, sulphide) ; zinc-spar {noble calamine, Smithsonite, carbonate,
and earthy calamine, hydrozincite, hydrated carbonate) ; siliciovs oxide
{ivillemite, anhydrous, and calamine, hydrated silicate).
Zinc-scum. The zinc-silver alloy skimmed from the surface of
the bath in the process of desilverization tjf lead by zinc.
Zinc-white. Oxide of zinc.
Zones. In a shaft-furnace, the ditt'erent portions (horizontal sec-
tions) are called zones, and characterized according to the reactions
which take place in them, as the zone of fusion or smelting-zone, the
reduction-zone, etc.