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 students 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 Gunome-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.
This blade is healthy and nice balanced nice work.
according to the Kanzan sayagaki and Jyuyo token zuhu, this sword is the top ranking sword in his making swords during his life.
The blade is healthy without kizu and flow.
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Appraisal Quiz #249 (June 21th, 2013)
Who made this sword do you think ?
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Hints. ※The picture will be enlarged
Blade length : 75.3 cm or 29.64 inches.
Sori : 2.5 cm or 0.98 inches.
Mekugi : 2
Width at the hamachi : 2.80 cm or 1.10 inches.
Width at the Kissaki : 1.87 cm or 0.73 inches.
Kasane : 0.71 cm or 0.27 inches.
Shape : The blade is long with deep sori nice looking wonderful shape.
On both side of the blade have Bo-hi and soehi are engraved.
Jitetsu :Itame had masa nagare with jinie attach and visible to see the texture.
Hamon : Koniedeki suguha with kasha work and boshi is round and sharp point like a candlewick.
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