Skip to main content

Validating minting ages of coins

XRD can be used to validate minting ages of coins. A 2005 US penny has a zinc metal core and a combination Cu/Nickel alloy coating. Before 1986, the US pennies were comprised entirely of a copper and zinc alloy. When looking at the diffraction patterns from a MiniFlex in the figures it can be seen that no zinc core was discovered in the 1985 penny.