Previous answer is
Mumei (Den Hosho)
Special feature: Hosho is the name of a group of swordsmiths in the koto period.
They worked in Yamato province. The founder was Kunimitsu who lived circa Koan (1278) of the late Kamakura period.
Hosho Goro Sadamune, Saemon no jyo Sadayoshi and Fujiwara Sadakiyo were his sons who were also worked as the principal smiths of this school.
They were good at masame-hada kitae. Quite a few tantos survive but their Tachi is extremely rare.
Regularly patterned masame-hada includes nie appears on the whole part of the blade.
The different point between koto Hosho-mono and Shin-to is hada-ware.
Masame does not stick with hada. Boshi appears along with masame that approaches to the mune.
The point is hakikake, yakizume with much nie.
Appraisal Quiz #571 (January 11th, 2020)
Who made this sword do you think ?
Blade length : 68.2 cm or 26.85 inches.
Sori :1.8 cm or 0.71 inches.
Mekugi : 2
Width at the hamachi :2.87 cm or 1.13 inches.
Width at the Kissaki : 2.4 cm or 0.94 inches.
Kasane : 0.53cm or 0.94 inches.
The weight of the sword 645 grams.
Shape : The blade is oosurigae and suitable width
and thick with deep sori and long Kissaki.
On both sides of the blade engraved Bo-hi and Soe hi.
Jigane :Itame hada well grained with jinie attach and chikei work wonderful fine Jigane.
Hamon :Nie deck deep nioikuchi with sunagashi and Kinsuji work looks like
Go. Bo-shi is noter double hamon, from the middle part to Kissaki area, very active fine deep nioikuchi ash and soft Habuchi.
Bo-shi is noter double hamon round hakikake style.
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