tes, India,
and Spain; and as a by-product in the electrolytic refining of the
Sudbury, Canada, nickel ores. The extension of this method of refining
to all of the Sudbury ores would create an important supply of platinum.
The Colombian output has been increasing rapidly since 1911. Meanwhile
the Russian production has declined; and from the best information
available, it is not likely that Russia will be able to maintain
production for many more years. Estimates of the life of the Russian
fields are from 12 to 20 years at the pre-war rate of production.

The platinum situation is commercially controlled by buying and
mine-operating agencies,--the French having, before the war, practically
dominated the Russian industry, while American interests controlled in
Colombia. The situation is further influenced by four large refineries,
in England, Germany, United States, and France.

Before the war the United States produced less than 1 per cent of the
new platinum it consumed annually. Production comes principally from
California, with smaller amounts from Oregon, Alaska, and Nevada. The
many efforts which have been made to develop an adequate domestic supply
of this metal do not indicate that the United States can ever hope to
become independent of foreign sources for its future supplies of
platinum.

There is little reason to doubt that the Colombia field, commercially
dominated by the United States, holds great promise for the future. The
output has come largely from native hand labor, and with the
installation of dredges can probably be greatly increased.

During the war, the need for platinum for war manufactures was so urgent
and the production so reduced, that restrictions against its use in
jewelry were put into force in all the allied countries. The United
States government secured quantities of platinum which would have been
sufficient for several years' use if war had continued. With the
cessation of hostilities restrictions on the use of platinum were
removed, and the accumulated metal was released by the government from
time to time in small quantities; but the demands for platinum in the
arts were so great that prices for a time tended to even higher levels
than during the war. More recently supply is again approaching demand.

GEOLOGIC FEATURES

Platinum, like gold, occurs chiefly as the native metal. This is usually
found alloyed with iron and with other metals of the platinum group,
especially iridi