How can you tell if your penny is made out of copper?

Get it to rust: Green rust: copper, red rust: iron, no rust: silver.

Not exactlyUS cents don't rust (except for 1943 ones). "Copper" pennies are made of bronze which oxidizes to the familiar dark brown color. And US cents have NEVER been made from iron or silver. Plus letting a coin oxidize is a sure way to destroy any collector value it may have.

The best way to tell is by the penny's date and/or weight.

• Cents up to 1857 were pure copper
• Cents from 1858 to mid-1864 were made of copper-nickel
• Cents from mid-1864 to mid-1982 (except for 1943) were made of bronze.
• Cents made in 1943 were struck in zinc-plated steel due to wartime shortages.
• Cents made since mid-1982 are zinc with a thin copper coating.