Thanks for all the input. I've searched everything that's been suggested and can't find anything of merit. Although, adding soapstone as a keyword did turn up something interesting... An Icelandic stone oil lamp!! Now, I know Iceland is not exactly a stones throw away... (Pun clearly intended). But we are sitting on about 50 feet of glacial till...so... It's possible. However, I'm pretty sure it's blue limestone which is quite common in the area. There is a limestone quarry about ten miles north of the site and hueston woods state park is even closer. I would think most of the fossil collectors would be familiar with hueston woods as it's well known in the fossil community and deservedly so, it's a treasure in itself.