Previous answer is
Nagamitsu
長光

Features:　Koto: Saijo saku: Owazamono: Bizen
Nagamitsu is said to be the son of Mitsutada, the founder of Osafune school. He left more works with signature than other swordsmiths of the same period. His works were consistently excellent. He had famous dischiples such as Kagemitsu, Chikakage and Masanaga, and some of Nagamitsu's works were made of them.
This Tokubetsu Juyo Token (Special Important Sword) comes with an origami (certificate) by Ami Mitsutada dated Genroku 12 (1699).
It has a wide blade and thick kasane, with a deep curvature and extended kissaki, exhibiting an excellent overall shape.
The mei (signature) is also superb.
The blade has no grooves (hi), and because of the presence of shinogiji, the jigane (steel texture) of the mid-Kamakura period can be clearly observed.

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Appraisal Quiz #869 (October 18th, 2025)
Who made this sword do you think ?
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Blade Length: 1 shaku 3 sun 7 bu – 41.5 cm (16.34 in)
Curvature: 2 bu 5 rin – 0.76 cm (0.30 in)
Mekugi Hole: 1
Width at Base (Motohaba): 3.1 cm (1.22 in)
Thickness (Kasane): 0.59 cm (0.23 in)
Sword Weight: 320 g
Shape: Slightly extended in length.
Jigane: Itame hada with visible grain. One side shows what appears to be an embedded gold (umegane) area.
Hamon: Matching hamon on both sides.

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