I have a 1898 Indianhead penny on the non-face side I think it’s called obverse side at the bottom it there is a stamp hard to see this coin has been in my family for over 30 years maybe longer and has only been handled a few times. I cannot find anything on this mark for this date inerrors or mints
Welcome Appears to be a ding (post mint damage) to the coin that is very worn and has been cleaned in its past. Cool coin to hang on to, especially since it’s been in your family for so long.