Yeah, I wasn't convinced to buy it until consulted with several kind gentlemen.Really !
A little off topic but I doubt that a 2.45 micron synth stone could give best mirroring result on core than a 0.49 micron one.
Very surprised by this but very interested because I was planning to buy a 30,000 thinking it could be the ultimate synth for mirroring core steel.
In my previous post, the shapton HC 6k was used to initiate the mirror, and Okudo suita was to convert tiny scratches to JNat pattern, so you see no visible scratches (but do have a polished frosted JNat finish at one specific light angle).
My 30000 was from the shapton seven series, 0.44 micron. It gives a total mirror, but the problem is, at the same specific light angle, you'll see crazy scratches (like ~ 1000 grit). That's totally unacceptable. I did much trial and error, and convinced that the scratches are from the 0.44. Glad I didn't waste too much money...
HC 6k still has some scratches, but no where as bad as the 0.44, easily erasable by the suita.
Not sure if the full sized 30000 glass stone performs the same though.