Found this roll hunting and was wondering on your thoughts if this is an error coin worth keeping or just another quarter? Thanks for your help
These come up fairly frequently. Our friend Chris, @cpm9ball wrote up a nice reply in the following thread which might help you too. https://www.cointalk.com/threads/er...die-struck-thru-grease-is-it-worth-it.193662/
I found the grease struck one that says, "in God We Rust." Neat to see there is another out there with just "UST" Neat!
Personally, I would keep it and stick it with my other error coins. It might not have any monetary value beyond face, but it's cool nonetheless.
There are some listed on ebay starting at 3.00 and up to 49.00. Don't know who would buy them, but people do. The cool thing most are just "RUST." The one I have is an uncirculated encased one from the US mint. As some don't desire these, there are others that do. I even had others asking about my dime (Avatar).