A Mago’emon Kiyomitsu Katana (備前国住長船孫右衛門尉清光作)

Here is an extremely powerful katana from the late Muromachi period, dated on a lucky day in August of the 13th year of Eiroku (1570) by the superior swordsmith Bizen Kiyomitsu. What makes this piece immediately collectable is its rare zokumei signature – signed with Kiyomitsu’s personal name Mago’emon no jô rather than his professional smith name alone. Such zokumei pieces were custom-ordered by high-ranking samurai and are regarded as the finest examples of any smith’s output. Kiyomitsu Mago’emon was the son of Gorôzaemon Kiyomitsu and flourished during the Eiroku era (1558-1570), this blade dated to the very peak of his career. He is ranked jô-saku and wazamono, recognised both as a superior smith and for the exceptional sharpness of his blades.

The blade itself commands attention. Its formidable structure carries a thick kasane (spine) that has comfortably withstood more than four and a half centuries, weighing an impressive 900 grams. The smoky suguha-kuzure hamon – a deliberately crumbling straight temper line that wisps along like smoke from a burnt-out candle – is interwoven with dancing kinsuji, falling leaves of yô, and ashi (legs) reaching toward the cutting edge. A faint Bizen utsuri appears along the back of the blade in faithful acknowledgement of classical Osafune tradition. The well-forged jihada of itame and mokume with chikei is everything one expects of late Bizen quality work.

The katana is accompanied by an outstanding dragon koshirae: a polished raw copper tsuba by the Hikone school in a spectacularly detailed dragon motif, certified NTHK-NPO Kanteisho to the late-Edo period (circa 1780-1867); a silver fuchi-kashira with unryû (cloud dragon) motif crafted and signed by Ishiguro Koretsune (1780-1867), itself certified NTHK-NPO Kanteisho; and matching dragon menuki. A sayagaki by Dr Satô Kanzan, written in autumn 1965, confirms this as one of the masterworks of Eiroku Kiyomitsu.