Previous answer is
Mumei(Naminohira)
Special feature:The founder of Naminohira School was Masakuni who moved
from Kyoto to Satsuma province in the10th century.
His works rarely survives so Yukiyasu is thought as the substantial founder.
The school continuously made swords there until the last Edo period.
The name Naminohira has synonymous meaning with the glassy surface
of the water so water transporters and navy men highly appreciate the sword of this school.
The special feature of Naminohira School is its traditional Suguha-hamon
and well-grained blackish Jigane.
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Appraisal Quiz #460 (October 14th, 2017)
Who made this sword do you think ?
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Hints. ※The picture will be enlarged
Blade length : 65.4 cm or 25.75 inches.
Sori 1.6 cm or 0.63 inches.
Mekugi : 1
Width at the hamachi : 2.84 cm or 1.12 inches.
Width at the Kissaki : 1.965 cm or 0.77 inches.
Kasane : 0.555 cm or 0.22 inches.
Shape : The blade is rather short size regular width
and thickness with deep sori and longer kissaki.
Jigane :Koitame hada well grained with jinie attach
and chikei work and also aranie on the ji.
shinogiji:Itame hada with masame hada mixed.
Hamon :Niedeki gunome midare and in Hamon, sunagashi kinsuji work.
Boshi is notare and pointed sharply and turnss back.
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