Previous answer is
Mumei (Rai Kuninaga)
Special feature: Rai Kuninaga was a student of Rai Kunitoshi and he moved to Settsu Nakajima province, so he was called Nakajima Rai.
Compare with Rai Kunitoshi and Rai Kuniniga, Hamon and Jigane are different.
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Appraisal Quiz #641 (May 22nd, 2021)
Who made this sword do you think ?
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Blade length : 74.6 cm or 29.37 inches.
Sori :1.67 cm or 0.65 inches.
Mekugi : 3
Width at the hamachi : 2.81cm or 1.10 inches.
Width at the Kissaki : 1.33cm or 0.52 inches.
Kasane : 0.74cm or 0.29 inches.
The weight of the sword 645 grams.
Shape : Ubu Nakako, regular width and thickness blade with deep Sori.
Jigane : Ko Itame hada well grained with Jinie attach. There are Usturi.
Hamon : Ko Nie Deki, Choji Midare with soft Ashi.
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