Sumitani Masamine

Sumitani Masamine (1921–1998) was a master swordsmith representative of the modern era (Showa–Heisei periods) and was designated a Living National Treasure (Jūyō Mukei Bunkazai Hojisha) for his sword-making technique in 1981 (Showa 56). Born in Matsutonishi City, Ishikawa Prefecture (now Hakusan City), he is a figure whose name remains indelibly inscribed in Japanese sword history as a swordsmith who inherited and revived the authentic Bizen tradition in the modern age.

Masamine's life was devoted to the revival of Japanese sword-forging after its decline following the sword-prohibition edicts. Training under his master Sakurai Masayuki, Masamine continued the path of sword-forging even during the postwar chaos. He conducted exhaustive research into the style of Old Bizen and Osafune, dedicating his life to the restoration of the precise chōji-midare patterns and utsuri luster that the Osafune school of the Kamakura period had mastered.

The defining characteristic of Masamine's swordwork was the recreation of the splendid chōji-midare patterns distinctive of the Bizen tradition. The jigane, with tightly compressed ko-itame, displays a bright and lustrous surface, with utsuri rising from the ji—manifesting the characteristic Bizen complexion. The hamon develops diverse chōji variations including large ō-chōji, frogspawn kawazuko-chōji, and reverse saka-chōji, with a bright, clear nie-guchi running evenly along the blade edge. His rigorous, archaistic restoration modeled on masterworks of the Old Bizen and Osafune periods achieved what the sword world had deemed impossible: the successful recreation of Kamakura-period chōji patterns, a feat that made a profound impact on the sword community.

Moreover, Masamine conducted distinctive research into tamahagane quality control and furnace-temperature management during the forging process, attempting to recreate the iron-working techniques of the ancient-sword period. While the tamahagane supplied by the Nihonto Hozon Kai is reconstructed tamahagane used by modern swordsmiths, Masamine established forging techniques that maximized the potential of this tamahagane and made significant contributions to the training of subsequent generations. Many swordsmiths emerged from his workshop.

His swordwork centered on Bizen chōji while also including a considerable number of examples in the gentle straight-edge style of the Yamashiro and Yamato traditions, testifying to the breadth of his technical mastery. Signatures include "Masamine" and "Bizen Osafune-jū Masamine," and his works are widely held in private and museum collections. The Token Hakubutsukan houses multiple representative works by Masamine, and he continues to be regarded today as a pinnacle of modern sword-making.