Here are 2 1990 and 2 1975 pennies, if you look you will notice that 1 of each date seems to be made of different metal. Kinda interesting, feedback is welcome and appreciated.
I believe they are all struck in the same metal - they are just in different states of condition. One of the coins appears to be full mint red - one appears to be most mint red - the other two appear to be worn, circulated and toned brown.
The only difference being that the 1975 issues are .950 copper and .050 tin and zinc. The 1990 issues are composed of a 99.2% zinc and 0.8% copper core, clad with pure copper.
