Previous answer is
Mumei (Niou)
Nio school was active from Kamakura period via Nanbokucho period to Edo Peirod.
The group has strong Yamato style work. Boshi is Yakizume work.
This piece is suguha style with active work in the ha.
The jigane is strikingly good with much brightness and smoothness.
Shinogi-ji is Itame hada alike the Jigane. This work reminds of Muku Kitae(Same as Maru Kitae.
Blades made of one steel) and moreover, it is unusual to see much Ubu Nakago shape work of that period.
There is no Bo-Hi groove in the Shinogi which allows us to clearly observe the Jigane work.
This sword was qualified as the latest 60th Jyuyo Sword so the
certificate will be arriving later.
It is incredible Ubu shape and the jigane is outstanding.
It is healthy masterpiece work.
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Appraisal Quiz #337 (April 19th, 2015)
Who made this sword do you think ?
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Hints. ※The picture will be enlarged
Blade length : 68.8 cm or 27.08 inches.
Sori : 1.2 cm or 0.47 inches.
Mekugi : 2
Width at the hamachi : 2.8 cm or 1.10 inches.
Width at the Kissaki : 1.98 cm or 0.77 inches.
Kasane : 0.75 cm or 0.29 inches.
Shape : The blade is elegant shape.
Jitetsu : Koitame had well grained with jinie attach and wonderful Utsuri appear.
Hamon : Noideki gunome mmidare and Cyoji midare mixed with kasha work.
Boshi is midarekomi and togari and turns back.
Who do you think made this sword?
1: He is very skillful sword maker both Bizen, Sosyu and Yamato school.
2 : In case of Bizen cyoji midair hamon, the blade has nice Utusuri appear on the ji.
3 : Nakagojiri is Kurijiri.
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