In 1982, the US mint transitioned from from an alloy of 95% copper and 5% zinc to a 100% zinc core electroplated with a coating of 100% copper. The copper penny will weigh 3.1 grams and the copper plated penny will weigh 2.5 grams. A scale will tell you what yours is made from.
Lincoln cents bearing no mintmark were struck in Philadelphia. (Exception: 2017 is the first and only year that the Philadelphia Mint will use a "P" on the cent, reverting to no mintmark in 2018.) Your coin could be 95% copper or 95% zinc. It was the transition year for the Lincoln cent in which both compositions were used. From 1983 to date, the cent is the crappy (meaning lousy surfaces that so many people mistake for errors) Zincoln! The only way to know for sure would be to weigh it. 95% copper cents should weigh 3.11 grams; 95% zinc cents should weigh 2.5 grams. Chris
