Previous answer is
Mumei (Unsigned) (Den Nagamitsu)
無銘(伝　長光)

Features: Nagamitsu is traditionally regarded as the son of Mitsutada, the founder of the Osafune school. Compared with other Kamakura-period smiths, a relatively large number of signed works by Nagamitsu survive, displaying consistently high quality and exceptional skill. His workmanship ranges from flamboyant styles reminiscent of Mitsutada to calm suguha. His disciples are said to have included Kagemitsu, Chikakage, and Sanenaga, and some works attributed to Nagamitsu are believed to have been produced by these pupils. This sword has been designated an Important Art Object. As a masterpiece attributed to Nagamitsu, the magnificence of its midare hamon is unsurpassed among examples the owner has encountered.

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Appraisal Quiz #907 (July 25th, 2026)
Who made this sword do you think ?
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Blade Length: 69.4 cm (27.32 in).
Curvature: 2.4 cm (0.94 in).
Mekugi Hole: 2.
Width at Base (Motohaba): 3.05 cm (1.20 in).
Width at Yokote: 1.81 cm (0.71 in).
Thickness of rim (Kasane): 0.65 cm (0.26 in).
Sword Weight: 715 g.
Shape: A magnificent blade with a wide mihaba, thick kasane, deep curvature, and a long kissaki, giving it a powerful and imposing appearance.
Jigane: Well-forged ko-itame hada mixed with mokume hada, producing a dense and refined steel surface. Utsuri is clearly visible. The shinogi-ji displays a finely forged masame hada.
Hamon: Nioi-deki suguha with gentle ko-ashi working actively throughout. The activities within the hamon are rich and varied.

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