Old Copper Culture artifacts (4000 B.C.-1000 B.C.) Manitoba Old Copper Culture artifacts have been recovered in Wisconsin as well.
Several 'native american' cultures in central & South America were extremely skilled in metal arts. Here's one example.
First off, I don't count gold.
But, If you're telling me that there are copper knives and spears in canada from 4000BC, that really would be something impressive and quite shocking...but honestly I don't beleive it, since the pilgrims were shot at with stone arrows in AD1600s. I guess I'll wait and see how well this claim stands up to scientists criticisms.