Thread: Hone ID?

I received this stone in a lot of mainly vintage man made
woodworking stones. It struck me as odd, being that it is a little over 10 inches long and an inch wide. As I was cleaning the years of crud off of it, a noticable sparkle started shining through. Once clean and lapped, it seems like it is a natural stone and is as smooth as a well burnished arkie. It is dark gray when dry and black when wet. Any help identifying it would be appreciated.
Dry:
Wet:
Close up wet:
With slurry raised, which is very fine and muddy:

Just shaved with one of my test razors off of this hone. The razor has always been kind of chippy and liked drawing blood. Thirty passes on whatever this stone is and it gave me an incredibly smooth shave. It's definitely a hone that deserves more testing.

Looks like a Pike's Black Diamond. I have one, I use it to sharpen fish hooks.