Wow - great posts. It's kind of late, so I'll just make a short reply and be back with better pics and more information tomorrow.

At first, it didn't seem like I could scratch it with a pocket knife, but when I took the tip of an old chef's knife and leaned into it, it did indeed scratch the surface.

I'm going to try to hook up with Superfly here about it. I think he told me once that he knows somebody who's cut hones for him before.

Thanks for all the info!