Previous answer is
Signature: Tenmei Goken Seitan no Yokei Fujiwara Nagasada.
Forged in Kyoto on an auspicious day in the first month of Meiji 2 (1869).
天明御釼精鍛之余慶藤原永貞
明治二年正月吉辰於京師造之

Features: Fujiwara Nagasada was a descendant of the Akasaka Senjuin lineage of Mino Province. Born in present-day Tarui, Gifu Prefecture, his personal name was Matsui Jiichirō. He was born in Bunka 6 (1809).
Many of his blades bear the inscription "Goshōzan Sanroku" ("At the Foot of Mount Goshō"), referring to the site where Tokugawa Ieyasu is said to have commanded his army during the Battle of Sekigahara. Around the Kōka era (1844–1848), Nagasada moved to Edo and studied under Taikei Naotane. He refined his swordmaking skills in Aoyama, Edo, and later became an official swordsmith to the Kishū Tokugawa family. He passed away in June 1869 (Meiji 2) at the age of 61.
Nagasada was highly regarded as a conscientious swordsmith whose works were consistently of high quality, with no inferior pieces. It is even said that some of his finest blades had their signatures removed and were later attributed as superior Koto works. As a result, comparatively few signed examples survive today.

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Appraisal Quiz #914 (September 12th, 2026)
Who made this sword do you think ?
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Blade Length: 2 shaku 2 sun 9 bu (69.4 cm (27.32 in)).
Curvature: 6 bu (1.8 cm (0.72 in)).
Mekugi Hole: 3.
Width at Base (Motohaba): 2.69 cm (1.06 in).
Width at Yokote: 1.91 cm (0.75 in).
Thickness of rim (Kasane): 0.51 cm (0.20 in).
Sword Weight: 540 g.
Shape: A katana with a slightly narrow mihaba, a substantial kasane, and graceful curvature.
Jigane: Itame hada mixed with flowing masame. Faint midare-utsuri is visible. Double grooves (futasuji-hi) are carved on both sides of the blade.
Hamon: Nie-deki, based on suguha with angular gunome-midare. The hamon shows sakagakari, with active ashi and yō.

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