What is the value of a 1966 US nickel with a rotated reverse?

Answer 1

I'm assuming that you are familiar with standard U.S. die orientation: The U.S. uses what's called "coin rotation", where circulation coins are struck with the reverse "upside down" with respect to the obverse. That is, if you hold the coin so that the obverse is correctly oriented and flip the coin from left to right like a book page, the image on the reverse is inverted. My apologies if I'm saying something you already know, but there have been many posters who became confused when they compared a U.S. coin to one from a country that uses "medal rotation" where the obverse and reverse point the same way.

Anyway, iff your nickel does not follow that pattern (compare it to other coins in your pocket change) it's likely to be a rotated die error. A 90-degree error (i.e. the reverse is oriented sideways instead of being inverted) is known for 1966 Jeffersons and retails in the $30 to $70 range depending on condition.

However, you'll have to take your coin to an expert who specialized in error coins and have it authenticated, because an increasing number of fake rotated-die "errors" have been appearing. They're made using the same technique as a 2-headed magician's coin, except that the correct sides are joined and rotated rather than swapping in a second obverse.