I have the above mentioned small cent with the st missing from the word trust. The coin is not ms-65 probably closer to ef-40 with slight wear on obverse the "S" in States and the "E" in E Pluribus Unum. I found reference on the internet to this coin having other errors,but not missing letters. It does not appear to be altered by a third party. If authentic, what is it worth?
If it is indeed a mint error, it'd probably be a grease filled die/struck through grease. Not rare, would maybe command a slight premium.
We need pictures to tell for sure, but it sounds like a struck through grease. Worth around $1.00 to the right person. Again, pics are needed though.