Grit Table / oilstones / India oilstones
Product, no maker data
Aluminum-oxide oilstone (Norton)
Norton publishes no micron for India stones. The values are CAMI-grit conversions from the coarse, medium, and fine labels, so ranges and estimates, not measurements.
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.
Range 116 to 141 µm. Grade ~ CAMI 100-120 by attested grit label; micron from CAMI conversion (CAMI 100 = 141, 120 = 116 µm).
Range 66 to 93 µm. Grade ~ CAMI 150-180; micron from CAMI conversion (150 = 93, 180 = 78, 220 = 66 µm).
Range 23.6 to 36 µm. Grade ~ CAMI 320-400; micron from CAMI conversion (320 = 36, 400 = 23.6 µm).