Previous answer is
　 Hizen Koku Ju Fujiwara Tadahiro
肥前国住藤原忠廣

Special feature : This blade is the early word of the 2nd generation Omi Daijo Tadahiro. Tadahiro was called Heisakuro and was the son of the 1st Tadayoshi. He was 19 yeard old when his father died in Kanei 9th year.
His sword has existed since the Kanei 10th with the coopperation of his school.
He recievd "Omi Daijo" in June Kanei 18th year.
He passed away in Genroku 6th at the age of 81.
The blade has nice Jigane and Hamon. This blade is before Omi Daijo" received.
The difference between the 1st Tadahiro and the 2nd Tadahiro should be noted for the 藤(Fuji) and 広(Hiro).

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Appraisal Quiz #678 (February 12th, 2022)
Who made this sword do you think ?
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Blade length : 35.5 cm or 13.97 inches.
Sori : 0.8 cm or 0.31 inches.
Mekugi: 1
Width at the hamachi : 3.24 cm or 1.27 inches.
Width at the Kissaki : 2.85 cm or 1.12 inches.
Kasane : 0.74 cm or 0.29 inches.
Shape : This blade is rather wide and thick Wakizashi with rather long Kissaki.
Jitetsu : Very tight Ko-itame with Jinie and Chikei attach.
Hamon : Suguha with deep Nioikuchi. There are many Sunagashi.

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