Roger Weller, geology instructor
firstname.lastname@example.org copyright 2010-R.Weller
copper in basalt
Keweenaw Peninsula, Michigan
One of the modes of occurrence for native copper in the mines of northern
Michigan was copper filling gas bubble pockets in a vesicular basalt. The
malleability of copper was then used in the processing of this type of ore. The
material was subjected to powerful stamping machines. The brittle basalt was
powdered by the process, while the malleable copper was simply flattened by
the stamping. The powdered basalt was then simply separated from the larger
and heavier pieces to flattened copper.
Photo is copyright free for non-commercial educational uses.
Just credit photo to R.Weller/Cochise College.