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ECONOMIC GEOLOGY

of Germany, France, and Spain, and along earth-movements
of the same age in the Eastern Highlands of Australia.
That platinum was raised in solution is suggested by the
fact that the ultra-basic rocks in which it is found have
been strongly altered, by its occurrence in various intermediate
 and sub-acid rocks, and with metallic sulphides in
quartz-veins, The fact that the metals with which it is
associated are mainly copper, gold, and chromium, in addition
 to its own kin, such as osmium and iridium, indicates
that the solutions which carried the platinum were of deepseated
 origin.