Previous answer is
　 Mumei(unsigned) attributed as Tametsugu　

Special feature: It is an accepted opinion that Tametsugu was a son of Go (No) Yoshihiro
and learned under Norishige though there is still room for more research about the difference of chrono-range among them.
Both Yoshihiro and Norishige were counted among ten brilliant pupils of Masamune.
Norishige created a peculiar texture of jitetsu compounded soft and hard iron commonly called matsukawa-hada
or Norishige-hada in Japanese. Tametsugu's works in Echizen province dated in 1357 and 1369 are still remain on the record as oshigata pictures.
An extant inscrived Noshu Ju Fujiwara Tametsugu in 1374 shows he moved to Mino province from 1369 to 1374 .
Judging from the texture of jitetsu,
this katana should be attributed to Hokkoku-mono,
forged in the northern province of Japan. Deep-nioikuchi,
thick nie, many sunagashi and kiusuji form an attractive temperline of Tametsugu.
Both jitetsu and hamon create a healthy impression.

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Appraisal Quiz #577 ( February 22nd, 2020)
Who made this sword do you think ?
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Blade length : 67.1 cm or 26.4 inches.
Sori : 1.2 cm or 0.47 inches.
Mekugi : 2
Width at the hamachi : 3.1 cm or 1.22 inches.
Width at the Kissaki : 1.99 cm or 0.78 inches.
Kasane : 0 68 cm or 0.27 inches.
The weight of the sword 665 grams.
Shape : The blade has Bo-Hi and Soe-hi on both sides of the blade.
Jigane :Ko itame hada well grained with jinie attach and chikei work.
Hamon : Nie deki wide suguha with thick nioikuchi and ashi work
and also sunagashi, kinsuji.
Bo-shi is round shape with thick nioikuchi.

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