Grit Table / naturals / Amakusa (天草)
Product, no maker data
Natural stone
No particle size in microns is published for this line. The values are our estimates from secondary sources, so the marks are faded and the spread is unknown.
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 16 to 29 µm. C-estimated ~#600 to #1000 depending on quarry/brand; finer, slower; foundation/medium stone.
Range 16 to 29 µm. C-estimated ~#800; coarser/faster than white.