Previous answer is
Mumei (Rai Kuniyuki)

Special feature: Rai Kuniyuki is the founder of Rai school.
There are some blade with inscription.
The blade was made around Kougen era(1256-1257).

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Appraisal Quiz #490 (June 2nd, 2018)
Who made this sword do you think ?
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Hints. ※The picture will be enlarged

Blade length :　64.6　cm or 25.43 inches.
Sori : 1.7 cm or 0.66 inches.
Mekugi : 1
Width at the hamachi : 3.1 cm or 1.22 inches.
Width at the Kissaki : 2.32 cm or 0.91 inches.
Kasane : 0.63 cm or 0.24 inches.
Shape : Osuriage, Mumei wide and thick Katana with large Sori.
The elegant shape, healthy Katana.
Jigane : The mixture of Ko-Itame Hada and Mokume Hada with
Jinie attach. Chirimen Hada. There are Usturi.
Hamon : Nie Deki, Suguha base with many Ko-Ashi.
In Ha, there are Ashi, Yo, Sunagashi and Kinsuji.
Boshi is round shape with thick Nioikuchi.
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Answer will be posted at next Appraisal Quiz.

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