What a mei contains
A typical mei contains: the workshop name (屋号, yago), often combined with the smith's given name; sometimes the steel type ('白' for Shirogami, '青' for Aogami); sometimes the region or city of origin; and occasionally a special designation ('本鍛' for 'true forge', '手打' for 'hand-forged', '無垢' for 'solid steel'). More prestigious makers use simpler stamps — their reputation requires no elaboration.
Reading direction
Traditional Japanese writing runs right to left, top to bottom. Most blade stamps follow this convention. When reading a three-character stamp on a blade, begin from the rightmost column and read downward, then move left. However, some modern Meiji-era and post-war makers adopted left-to-right Latin convention — always consider context.
Key characters to recognize
白 (shiro/haku) — white, as in Shirogami. 青 (ao/sei) — blue, as in Aogami. 鑿 (nomi) — chisel. 鉋 (kanna) — plane. 鋸 (nokogiri) — saw. 鍛 (tan) — forged/forging. 本 (hon/moto) — genuine/true. 上 (jō/ue) — superior grade. 極 (goku/kiwami) — extreme/highest grade. 作 (saku/tsukuru) — 'made by' — follows a smith's name.
The 'Hidari' (left) tradition
Some highly prestigious Edo-period marks are stamped in reversed/mirrored form — the 'Hidari' (left) convention. 'Hidari Ichihiro' is the most famous example. This tradition's origin is disputed: some scholars argue it derives from swordsmithing practice where blades were stamped from the 'inside' of the handle; others suggest it was a deliberate mark of prestige. Either way, a reversed stamp on a blade is generally a sign of antiquity and value.
Identifying unknown tools
When you acquire an unknown blade with an unrecognized stamp, begin with the form of the characters: pre-WWII stamps use traditional kanji forms (kyūjitai, 旧字体), while post-war stamps use simplified forms (shinjitai, 新字体). This dates the tool. Cross-reference with the Kanji & Steel blacksmith database, then consult the japanesechisels.com mei database and the Japanese auction market where stamps are frequently photographed and can be matched to known makers.
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