Natural "Ocean Blue" Tsushima sharpening honing waterstone whetstone Used for honing and sharpening knives, wood chisels, gouges, razors, blades, planes, fishing hooks (H) - extra hard, very dense, uniform consistency of ultra fine grit; longer life cutting edge; high dish resistance, long lifetime Quarried from a now closed underwater mine near South Tsushima Island, Japan; golden stamp of authenticity; very limited stock 8.0"x2.7"x1.0" (200x70x25mm), 2.2 lb (1.1 kg) +/- 5%; grit ~#10-12K (fine); H - extra hard (L4-4.5/5) Natural Sharpening Honing Pocket Stone Waterstone Hunting Knife Chisel Sharpener