In 1943, at the peak of World War II, zinc-coated steel cents were made for a short time because of war demands for copper. From 1944 through 1946, salvaged ammunition shells made their way into the minting process, and it was not uncommon to see coins featuring streaks of brass or having a considerably darker finish than other issues.
The cent’s composition was changed in 1982 because the value of the copper in the coin started to rise above one cent. In Fiscal Year 2013, the average one-cent piece minted cost the U.S. Mint 1.83 cents, down from 2.41 cents apiece in FY 2011.
The bronze and copper cents can be distinguished from the newer zinc cents by dropping the coins on a solid surface. The predominantly copper coins produce a higher-pitched ringing sound, while the zinc coins make a lower-pitched “clunk”.14 In addition, a full 50-cent roll of pre-1982/3 coins weighs 5.4 oz compared to a post-1982–83 roll which weighs 4.4 oz.
Fair-use Copy-and-Paste from…https://en.wikipedia.org/wiki/Penny_(United_States_coin)…one of the most interesting pages I’ve come across.
Cool penny trivia from Wikipedia…
1983–presentcopper-plated zinc; total: 97.5% zinc, 2.5% copperWeight – 2.5 grams
In 1943, at the peak of World War II, zinc-coated steel cents were made for a short time because of war demands for copper. From 1944 through 1946, salvaged ammunition shells made their way into the minting process, and it was not uncommon to see coins featuring streaks of brass or having a considerably darker finish than other issues.
The cent’s composition was changed in 1982 because the value of the copper in the coin started to rise above one cent. In Fiscal Year 2013, the average one-cent piece minted cost the U.S. Mint 1.83 cents, down from 2.41 cents apiece in FY 2011.
The bronze and copper cents can be distinguished from the newer zinc cents by dropping the coins on a solid surface. The predominantly copper coins produce a higher-pitched ringing sound, while the zinc coins make a lower-pitched “clunk”.14 In addition, a full 50-cent roll of pre-1982/3 coins weighs 5.4 oz compared to a post-1982–83 roll which weighs 4.4 oz.
Fair-use Copy-and-Paste from…https://en.wikipedia.org/wiki/Penny_(United_States_coin)…one of the most interesting pages I’ve come across.