I cannot remember what this error is called...I found this in a box of pennies I went through last night and was excited when I saw it was a blazing BU 1955-S and then even more when I saw it was an error. Error is the blob on the 9 in the date. Photos attached - sorry they aren't great today.
It's worth a very little premium of around $1-2, but still hard to find because it is an error after all.