Previous answer is
Bishū Osafune Tomosada (Ko-zori)
備州長船友貞(小反り)

Features: According to the book "Kokin Kaji Shiko", Tomosada was active around the Ōei era in Bizen Osafune.
However, based on the workmanship and the style of the signature, this piece is presumed to be from the late Nanbokuchō period.
This tachi features a flowing itame and mokume jigane with visible hada and fine ji-nie.
Chikei-like small patterns appear, along with ko-ashi, ha, and fine nie, indicating high-quality workmanship.
The signature is also slightly small in size, further representing Tomosada’s style.
No other known examples of signed Tomosada exist, making this a rare and important reference for his work.
Tomosada belonged to the Ko-zori school of Bizen and is known for outstanding craftsmanship.
The hamon shows gentle gunome-midare, a visible utsuri, and a deep curvature, forming an elegant blade.
This sword also comes with a sayagaki by Dr. Kunzan.

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Appraisal Quiz #866 (September 27th, 2025)
Who made this sword do you think ?
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Blade Length: 46.8 cm (18.43 in)
Curvature: 3.6 cm (1.42 in)
Mekugi Hole: 1
Width at Base (Motohaba): 3.14 cm (1.24 in)
Thickness of rim (Kasane): 0.77 cm (0.30 in)
Sword Weight: 775 g
Shape: This is a very rare and solidly made naginata.
It has a wide body and thick kasane.
Jigane: Well-forged and polished to the highest level.
Hamon: Ko-nie deki with deep nioiguchi, showing a soft texture like torn hōsho paper.

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Answer will be posted at next Appraisal Quiz.

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