Previous answer is
Bizen Koku Ju Osafune Genbei no Jo Sukesada Saku Kore.
A lucky day in August, Tensho 6 (1578).
備前国住長船源兵衛尉祐定作之也
天正六年戌寅八月吉日

Features: Genbei no Jo Sukesada was the son of Yosazaemon Sukesada and produced swords for the Uragami clan, lords of Tenjinyama Castle.
Although the Sukesada school represents Sue-Bizen and produced many mass-made swords, works like this bearing a secular name and date were commissioned by powerful warlords, made carefully with high-quality steel, and exhibit especially high skill.

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Appraisal Quiz #889 (March 21st, 2026)
Who made this sword do you think ?
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Blade Length: 66.0 cm (25.98 in).
Curvature: 1.2 cm (0.47 in).
Mekugi Hole: 3.
Width at Base (Motohaba): 2.88 cm (1.13 in).
Width at Yokote: 1.94 cm (0.76 in).
Thickness of rim (Kasane): 0.74 cm (0.29 in).
Sword Weight: 645 g.
Shape: O-suriage,
Jigane: Extremely well-forged, forming a refined steel close to muji-hada.
Hamon: A slightly deep nioiguchi suguha with well-formed ko-ashi and kuichigai.
The boshi turns back in a rounded manner.

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Answer will be posted at next Appraisal Quiz.

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