How do you tell the difference between a copper penny and a copper-plated zinc penny?

Answer 1

Well, there are two ways. You could scratch it or melt it over a flame to check composition. Or, you could check the date.

The first US penny was minted in 1793 and was 100% pure copper. In 1856 the cent's size was reduced and they were changed to an alloy that was 88% copper and 12% nickel, although pure copper large cents continued to be produced as well for one more year. The nickel alloy was hard to strike and the coins had a whitish appearance so in 1864 a bronze alloy of 95% copper and 5% tin and/or zinc was adopted.

In 1943 the US made the famous steel pennies. These were made for only one year and were zinc coated steel. There was a copper shortage because of the war. There were a few copper pennies made that year also and they are now quite valuable.

Bronze pennies were resumed in 1944. In 1962 the US stopped using tin pennies and they became just 95% copper and 5% zinc.

In the middle of 1982 the price of copper rose to the point where each penny contained more than 1¢ worth of metal. The composition was changed again to copper-plated zinc (97.5% zinc and 2.5% copper.) So, unless you have a US large cent it is in some way less than 100% pure copper. For more information about US Coins the US mint is the place to get answers. www.USMint.gov Anne

Boiled Down If it's dated 1982 or older, then it's copper ... If it's dated 1983 or newer, then it's zinc with a thin copper plate ... If it's 1982, weigh it -- if it's 3.1 grams then it's copper .. if it's 2.5 grams then it's zinc. Unless it is one of the few mistakes the U.S. made in 1983 when they made about 100 copper pennies that are very rare and expensive today.

Answer 2

Bronze is an alloy of copper and thus has a brown color. Zinc is an element and appears bluish white in color.