CHAPTER VIII

ORES OF FIVE MINOR METALS—NICKEL, MERCURY
ANTIMONY, ARSENIC, AND BISMUTH

Nicker—Uses anp Price—Nickel (Ni; at. wt, 59; sp.
gr., 8:4 to 8-8; melting-point, 2650° F.) is a widely distributed
 metal which occurs with native iron in the iron
meteorites and must form a considerable proportion of the
metallic barysphere. Although early used by the Chinese
for coins, it was not discovered in Europe until 1751, and remained
 scarce until the opening of the New Caledonia
deposits in 1890, and of the still richer mines at Sudbury
In Canada. In 1900 the world's production was 7500 tons;
In 1913 Canada produced 21,600 tons, New Caledonia 2700,
and Norway 700. During the War the output rose to 40,000
tons, and the price to £200 per ton ; but owing to the stocks
then accumulated, the output fell in 1921 to 5000 tons;
but it had risen to 36,000 tons in 1925, and the price is now
about £170 per ton. Nickelis whitein colour, hard and ductile,
and does not tarnish as it is not readily oxidized. Its main
use is in alloys, such as nickel-steel, of which the strength
1s largely due to its 3 per cent. of nickel. It lowers the cost
of metal structures by reducing the necessary weight. It
was long used mainly as German-silver, an alloy of nickel,
copper, and zinc. Nickel forms 36 per cent. of invar, a
metal used for scientific instruments, as it has the lowest
known coefficient of expansion. Grains of a native ironnickel
 alloy, Awaruite (FeNi,), are found in serpentine in
New Zealand.
_ Nickel has often been regarded from its association with
;'ON In meteorites as formed by direct igneous action. It
Is chiefly found in sulphides, especially pyrrhotite (magnetic
Pyrites), in which it is present as pentlandite ((FeNiS);
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