Word of advice - drop the '
no mint mark', it makes you sound like a clueless newbie who watched too many clickbait YouTube videos (or worse reads the Sun).
But at least you are here.
The Philadelphia Mint has never put its P mintmark on cents, except in 2017 to commemorate the 225th anniversary of the founding of the mint. So '
no mint mark' is just a normal Philly coin.
FWIW - except for the
War Nickels to identify them as 35% silver - they didn't mark any coins until the 1979
Susan B. Anthony dollars and then the other coins from 1980 onwards. Even today, some bullion coins don't have the "P".
-----Burton
50+ year / Life / Emeritus
ANA member (joined 12/1/1973)
Life member: Numismatics International, CONECA
Member: TNA, FtWCC, NETCC, EveryCountry (online) coin club
Owned by three cats and a wife of 40+ years (joined 1983)
Author: 3rd Edition of the Sample Slabs book,
https://www.sampleslabs.info/