David Weaver
This is a white suita from ohira mine. it's as thick as 8/4 planed lumber and is full of something known as blue renge. It's hard and fine and kind of finicky. The other okudo short stone shown in this picture series is more practical for day to day use, and I have this stone only because I'm not looking forward to the challenge of selling it for a reasonable price as it's nearly four figures and has rough sawn sides and will be just shy of 3 inches wide if I lap the sides.

I got it a while ago on a bender.

with a slurry, which is typical as the stone gets "grippy and skippy" without one and is hard enough not to raise its own slurry very quickly. it is a fine stone, though, about as fine as a natural japanese stone with fresh particles would be.

And then, just because I wanted to see if I could coax it into finer-than-it-is behavior, I experimented with something I learned a while ago with the sigma power stone - use the stone dry after the edge is finished. It can't be used dry first, it has to be done to its max as normal, and then used dry afterwards. The slurry dulling (that makes the flat part cleaner than the edge in terms of finish) stops and the edge becomes much sharper. If it's used wet without a slurry, it will not match this finish - it'll have bad use characteristics and continue to leave grooves to the edge.

the shaving behavior of the iron after this was fantastic, but it's not practical for woodworking (it took 2 minutes of extra work to get to this point) - remember that the washita does nearly as well in a total of 20 seconds.