All posts by Sarah Miller

Director of Numismatics, New York

What is Rainbow Coin Toning?

Read this article to find out what causes rainbow toning on coins, and how it effects the value.

1961 Franklin Half Dollar Proof Coin Value with Doubled Die Error on Reverse

After first hearing the definition of a “proof” coin, or a specially struck coin with mirrored surfaces produced by the United States Mint for collectors instead of for circulation, it becomes clear that such coins