Value is negligible - maybe a buck tops. Filled letters are caused by die chips and were very common from the fifties and into the sixties.
That was very common on the 1940s and 1950s cents. I keep nice examples but usually I just toss them into the junk bucket.
Weird. I just found one of these 1957 D in a roll and the b was filled exactly the same way. Not weird that I found the exact duplicate, just weird that a day later someone else posts one.
