“Two bills introduced in the US Congress would have ceased production of pennies, but neither bill was approved. Such a bill would leave the nickel, at five cents, as the lowest-value coin. On February 15, 2013, President Barack Obama stated his willingness to eliminate the penny.” - Penny debate in the United States - Wikipedia

“The cent's composition was changed in 1982 because the value of the copper in the coin started to rise above one cent. Some 1982 pennies used the 97.5% zinc composition, while others used the 95% copper composition.” - Penny (United States coin) - Wikipedia

“That made the value of copper in each penny worth about 1.4 cents. The meltdown value of a penny was 40% more than the face value. Copper moved to a higher price at the end of 2016 of around $2.70 per pound, making the value of copper in older pennies even higher.Aug 18, 2017″ - As Price of Metal Has Risen, Copper Penny Is Worth More Than One Cent - from the Balance.

"Over the last few years, the market for copper has skyrocketed. Just last January, the market peaked at $3.649 per pound. At 146 pennies to a pound, a single penny’s copper has a value of about 2.5 cents.
That’s not a bad deal! Get a penny for 1 cent and sell the copper for 2.5 cents? How often do you find an intentionally undervalued investment that is easily purchased?
If you think that making money on your pennies is too good to be true, there is a catch. It’s illegal to melt down currency and sell as scrap. Also, there is no crossing the border with your penny bags either. It’s illegal to leave the country with more than $5 in pennies. Most penny hoarders are stockpiling their currency in the hopes that the law will change and allow them to finally cash in on their stockpiles." - Why Some Americans Are Hoarding Their Pennies…. (Literally)