I have a list of metal bead suppliers that has links to many fine companies, but I notice that most of them specialize in silver and gold. Vintaj is listed, a wholesaler of brass beads and findings, and also Green Girl Studios, which has pewter delights as well as silver.
Here are some additional sources of copper, pewter, and brass:
Rings & Things
And for metal clays, including the new BronzClay and CopprClay, don't forget about Rio Grande!
Jean Campbell, at Beading Daily, has provided a wonderful chart which gives you the low down on copper, brass, and pewter, including how to care for them.
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