Grit Table / naturals / Tsushima (対馬)
Product, maker figures
Natural stone
The maker publishes these figures. A single value per grade, no distribution given, so each is drawn as a point.
Each grade below shows its size in microns, its spread (the published distribution, where a maker or standard gives one; most makers publish none), and where that size lands on the reference scale, a shared yardstick for reading grit numbers across makers.
Dealer states ~7.6 micron average slurry abrasive (Mohs ~8.2), used mainly as a nagura/slurry stone.