Previous answer is
Hizen Koku ju Oumi Daijo Fujiwara Tadahiro
Special feature: Tadahiro the Second forged this katana.
He was born Heisakuro Hashimoto as a legitimate son
of Tadayoshi the First. Tadahiro was only19 years old
when his father passed away in1632
but he was enough skillful to forge sword at that time. Tadahiro
designated the Omi-Daijo in 1641, aged 29 and continued not only
forging sword but also supervised many pupils until his death in 1693,
aged 80. He is known as a skillful swordsmith almost all works are
above the standard hizen-to. He had been forged sword for a long
period of time to leave the largest number of swords among the
swordsmiths of Hizen school. He was good at both of Suguha-hamon
and Choji-midare Hamon. Especially the beauty of jitetsu called
konuka-hada is appreciated as the best among the hizen-to. His
swords are ranked at the Owaza-mono because of the sharpness.
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Appraisal Quiz #558 (September 28th, 2019)
Who made this sword do you think ?
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Blade length : 71.5 cm or 28.14 inches.
Sori : 0.8 cm or 0.31 inches.
Mekugi : 2
Width at the hamachi : 2.89 cm or 1.13 inches.
Width at the Kissaki : 1.78 cm or 0.70 inches.
Kasane : 0.58 cm or 0.22 inches.
The weight of the sword:660 grams.
Shape : Regular width and thickness Katana with small Sori. Utsubuse Gokoro.
Jigane : Ko Itame Hada and Ko Mokume Hada well grained with Jinie attach.
Tehre are Utsuri. The Bo-Hi on the both side of the blade.
Shinogi-Ji: Itame and Mokume.
Hamon : Nie Deki, Suguha and Notere Ba. The Nioikuchi is soft.
In the Ha, there are Ashi, Yo, Sunagashi and Kinsuji.
Boshi is large Notare round shape.
Hints. ※The picture will be enlarged
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