The answer was
Moritsugu(Ko Aoe)

Special Feauture :
This school's signatyure is Katana mei but exceptionaly Aoe Moritsugu made Tachimei.

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Appraisal Quiz #434
Who made this sword?
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Hints. ※The picture will be enlarged

Blade length : 72.3 cm or 28.46 inches.
Sori : 1.7 cm or 0.66 inches.
Mekugi : 1
Width at the hamachi : 2.91 cm or 1.14 inches.
Width at the Kissaki : 2.03 cm or 0.79 inches.
Kasane : 0.74 cm or 0.29 inches.
Era : Late Nanbokucho period to early Muromachi period.
Shape : The blade is oosuriage mumei(cut shortened) the blade is rather wise and thick with deep sori and long kissaki nice looking shape.
Jitetsu :Itame hada and mokume hada mixed with jinie attach and small chikei work.
Hamon : Niede ki suguha hamo and notare ba mixed ther are many ashi,sunagashi Yo and also chikei work. Especially from Muneuchi area to Kissaki, active hamon work.Boshi is round shape and Yakusage deep.

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Answer will be posted at next Appraisal Quiz.

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