I believe it is a coin from Shun-chi 1644-1661, although such coins were minted in terms of MILLIONS.
The real trouble is to identify whether it is genuine or not, as well as to identify what it is. Counterfeited taels doesn't have to be iron, but...
No, not necessary. If there had been contamination from the postage from the mint to your place, or improper handling at the mint, perhaps the...
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