Mike,
According to Alex Gilmore, that tree ring pattern was shared by Narutaki and Nakayama, so maybe that 'thins the herd' a little when it comes to identifying the origin of the stone. Of course, nothing is certain with Jnats.
This is a re-hone of a Towa Scheon Burg frameback I got from Stefan and carried with me to France for a couple of weeks - it's a good shaver and I wanted nice shaves on the trip. When I bought it, I asked Stefan if he used tape and he said yes, one layer.
The tape in the image though is 1 mil DuPont Kapton, a wear-resistant and wonderful tape for razor honing. It's actually 1.2 mil and the adhesive makes it 2.7 mil total, but still less than half the thickness of most electrical tapes. An added bonus is that the razor feels more normal on the hones, and you can strop with it in place if you wish.
I re-set the bevel on a Shapton Pro 2k, then Shapton 5k/Shapton HC Glass 8k followed by koma nagura and tomo nagura on the finisher. I used one piece for the 2k stone, and the same piece for the 5k and 8k stones, and another for the finisher.
Et Voila! A great edge.
Cheers, Steve