corroded

This might work on nickel three-cent coins, too. Fatty Indian heads, too? They are ~12% nickel.

I recently unearthed this coin/token from an old home site (probably from 1930's), but the area has been inhabited for a long time before that (Ayer, MA). It was about 6"-8" deep. It's 1 mm thick, and 28 mm (1-1/8") in diameter (noticeably bigger than a quarter). But it's pretty corroded: the...