When I look at them...they look like "P''s...but under a lube...they seem to look like something else...they are marked on the left of the date....they're decent coins...so it's not just a mark...and they all have it.....as you can tell I just buy and sell them...without much knowledge of them, but they do look like a "P"...hope I helped...if you have any advice on this...or knowledge..let me know..I'm curious now,,,:).....Thanks for checking them out....Jim
The mark to the left of the date is JS, the designer's initials. A mint mark would be on the reverse. The mint mark P was not used on Roosevelt dimes until 1980.