How Much Copper Is In A Penny?

By GovMint :

Pennies, or one-cent coins in the United States, historically contained a significant amount of copper. Before 1982, pennies were composed of 95% copper and 5% zinc. However, the composition was altered in 1982 to 97.5% zinc with a thin copper plating to reduce production costs. This change was implemented due to the increasing cost of copper, which made it more expensive to produce copper pennies than their actual face value. Despite the shift in composition, pennies are colloquially still referred to as copper coins owing to their copper appearance.

Sources Used:

https://www.usmint.gov/learn/coin-and-medal-programs/coin-specifications 

https://www.coinflation.com/coins/1909-1982-Lincoln-Cent-Penny-Value.html