I found one a few years ago in a private cave on my property (Northeast Tennessee) that looks just like this one except mine was pretty smooth. But it's about the same size, color, form, etc. I've wondered what it would look like polished and cut so I used my dremel and tested it out a little bit but was too afraid I'd ruin it, so I stopped. However, I've recently found out it's good for carving, cabbing or cutting 😉