Stones &
Water

A coarse-grit splash-and-go stone for rapid material removal and geometry correction. The Glass Stone's hard vitrified binder resists dishing exceptionally well, making it far more durable than soft splash-and-go alternatives. The starting point for establishing a primary bevel or repairing a chipped edge.

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A hard, fast-cutting intermediate-finishing stone that bridges the gap between primary sharpening and mirror polishing. Exceptionally valuable for Aogami steels, where the extra carbides benefit from the aggressiveness of this grit before the final polish.

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The finest Chosera stone produces an exceedingly refined edge. Particularly effective for Shirogami steels, whose simple carbon structure responds to very fine abrasives with an almost surgical keenness. After this stone, only leather stropping remains. Used extensively by Japanese professional woodworkers who keep their tools sharp throughout a working day.

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The classic entry-level Japanese combination stone — 1000 grit on one face, 6000 on the other. The magnesia binder requires 10–15 minutes soaking before use. Soft and muddy; wears faster than vitrifed stones but the generous slurry helps beginners feel the cutting action. The industry standard starting point for thousands of Japanese tool enthusiasts worldwide. Not the final word, but an honest beginning.

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A diamond lapping plate used almost exclusively for flattening waterstones — not for sharpening tools directly. The 140-grit diamond surface removes high spots from even the hardest vitrified stones quickly. A flat stone is a non-negotiable prerequisite for consistent results. Every serious sharpening setup eventually acquires one of these. Also used to establish the ura-dashi (hollow back refresh) on Japanese plane blades.

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The more affordable Shapton line that shares the splash-and-go convenience of the Glass stones but uses a slightly different abrasive formulation. The 8000-grit Rockstar is an exceptional finishing stone for everyday use — slightly softer feedback than Glass stones, which some users find easier to control when applying a very light finishing stroke. Excellent value entry into serious high-grit finishing.

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Binsui (中砥) is a natural Japanese sandstone quarried from the Amakusa Islands. A coarse natural stone used for primary sharpening work. Unlike synthetic stones, natural stones vary from piece to piece and the Binsui produces a particularly aggressive, tooth-like edge that some craftsmen prefer for tools that need to grip rather than slice — like certain saw blades and roughing chisels. An authentic piece of Japanese lapidary tradition.

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Aoto (青砥) — 'blue whetstone' — is perhaps the quintessential natural Japanese finishing stone. Mined from the Aoto River region, the distinctive blue-grey colour signals its unique silica structure. Significantly finer than Binsui, the Aoto leaves an edge that Japanese craftsmen describe as possessing excellent 'tooth' — not a mirror but an aggressive keenness suited to cutting across grain. Master carpenters often end their sharpening sequences on Aoto rather than a mirror polish.

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