Hi I have a quarter from 1983 where the Mark is is just a round print maybe D that has no hole in the middle ?
Welcome to the neighborhood! A photo would help, but in all likelihood, the post that forms the center of the letter probably broke off the die, thus, allowing coin metal to flow into the void. This is a very common occurrence. Chris
Thanks Chris do not have coin on me now but will add a pic it looks like a raised period at the and of a sentence