sits of New
Caledonia. In this locality the original rock is a peridotite,
relatively low in nickel, which has been altered to serpentine.
Weathering has concentrated the more resistant nickel at the expense of
the more soluble minerals, and has produced extensive blanket deposits
of clay, which in their lower portions contain nickel in profitable
amounts. Similar processes, working on material of a somewhat different
original composition, have produced the nickel-bearing and
chrome-bearing iron ores of Cuba (pp. 171-173).

TUNGSTEN (WOLFRAM) ORES

ECONOMIC FEATURES

The principal use of tungsten is in the making of high speed tool
steels. It is added either as the powdered metal or in the form of
ferrotungsten, an alloy containing 70 to 90 per cent of tungsten.
Tungsten is also used for filaments in incandescent lamps, and in
contacts for internal combustion engines, being a substitute for
platinum in the latter use. Of late years tungsten alloys have also been
used in valves of airplane and automobile engines.

The average grade of tungsten ores mined in the United States is less
than 3 per cent of the metal; before smelting they are concentrated to
an average grade of 60 per cent tungsten oxide.

Germany through its smelting interests controlled the foreign tungsten
situation prior to the war; two-thirds of its excess output of
ferrotungsten was consumed by England and the balance principally by the
United States and France. Other consumers in the main satisfied their
requirements by imports of tool steel from these four countries.

The bulk of the tungsten ore consumed in Europe prior to 1914 came from
British possessions; these were principally the Federated Malay States,
Burma, Australia, and New Zealand. The United States, Portugal, Bolivia,
Japan, Siam, Argentina, and Peru were also producers. The great demand
for tungsten created by the war added China to the list of important
producers and greatly increased the production from Burma and Bolivia.
Smelting works were established in England and those of the United
States and France were greatly enlarged. England is at present in a
position to dominate the world tungsten situation. The question of
control of the ores obtainable in China, Korea, Siam, Portugal, and
western South America is likely to be an important one for the future.

Of the annual pre-war world production, the United States used about
one-fifth. Three-fourths of this requirement was m