bridger berdel
I live in a place with varied geology and some good hiking trails. A few times I've picked up rocks thinking that they would make a good finishing hone. A few have, most not so much. The latest batch seem like a pretty good bet. I've sliced up a couple of chunks on the tile saw. The next step is to lap a flat face to 600 grit or so and see just what it is that I've got here. David, I know you have a good microscope and a fairly in depth knowledge and feel for natural finishers. If you're willing I'd like to send you a lapped bit of what I have, for you to play with. I'm not going to try to make any kind of commercial endeavor of this as I don't have available material at scale. Mostly I'm trying to satisfy my own curiousity but I guess I have a bit of desire to encourage others to play with found rocks.

Just what you need, anther rabbit hole, eh?