Just to make sure that you know.. It's not struck on a Copper Planchet intended for a Cent. If it were it would be the same Size, Thickness and Weight of a Copper Cent Planchet. Could be a Improperly Annealed Planchet or some toning due to Environmental Damage. Hard to determine. Your second pictures make the Nickel look more yellowish than coppery.. Oh.. I Just read your response on the lighting difference.
It's toning, the spots on it, say the toning was induced and not natural. I wouldn't pay a premium for it.
It is not on a cent planchet. It is also not on cent stock. And I am pretty sure it isn't improperly annealed. Me thinks just damage