statistical
purposes, however, to point out the mistake of the usual platinum miner
in speaking of iridosmine as " iridium." It should be borne in mind
that iridosmine is an alloy of osmium and iridium, with percentages of
osmium varying from 17 to 49, as described by J. F. Kemp.1
There is practically no market for osmium, except the use as pen
points; therefore iridosmine is only valuable for the iridium
contained. The extraction of osmium is very costly, and also dangerous
on account of the poisonous character of the osmium vapor.
Palladium.—The
supply of palladium available for trade increased slightly on account
of the greater care taken in treating the slimes of copper refineries.
The palladium is found with gold, silver, etc., and in the slime of
Canadian matte, and also from the base bullion from Australia and
elsewhere. The use of palladium as a catalyzer is well known, and it is
much in favor for this use. Its consumption has also increased as an
alloy for platinum for ornamental purposes, as it renders the platinum
lighter and of a more brilliant white.
Osmium.—The
supply of this member of the platinum group is in excess of the present
demand, because tungsten has replaced it for filaments in incandescent
lighting, and its use in medicine and in silk dyeing is extremely
slight.
lV. S. tteol. Survey Bull. 103, p. 26, 1902.
