Join Date: Dec 2004
Location: Santa Barbara, California
I have heard of one technique that (supposedly) was used in Japan:
Micro-meteorites fell to the earth and were washed into rivers; and these small nickel-iron meteorites were recovered by dragging large magnets through dry river beds in summer, when the rivers were dry. The resultant iron could be incorporated with other iron, and because of its high nickel content could be processed and refined by forge-folding.