Previous answer is
Bishu Osafune Hidesuke
Ouei 11 Nen 2 Gatsu Hi(February, 1404)
備州長船秀助
応永十一年二月日

Features: Bishu Osafune Hidesuke was a swordsmith active from the late Nanbokucho to early Muromachi period.
This work is dated February, 1404 (Oei 11), and features a clearly engraved signature on both the omote and ura sides, which is especially impressive.
The blade has an elegant shape with deep curvature.
With a blade length of 72.3 cm, it is considered long for a work from the early Muromachi period and is thus a rare and valuable piece.

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Appraisal Quiz #858 (August 2nd, 2025)
Who made this sword do you think ?
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Blade Length: 69.5 cm (27.36 in)
Curvature: 0.6 cm (0.24 in)
Mekugi Hole: 2
Width at Base (Motohaba): 2.84 cm (1.12 in)
Width at Yokote (Sakihaba): 1.84 cm (0.72 in)
Thickness of rim (Kasane): 0.53 cm (0.21 in)
Sword Weight: 570 grams
Shape: The blade has two grooves (hi) lacquered in red.
It features an extended Kissaki (tip).
Jigane: Itame hada mixed with Mokume hada, representing the Taima school.
Utsuri (shadow pattern) appears.
Hamon: Primarily in suguha (straight line), with elements of notare (wave), hotsure (fraying), uchinoke, nijuba (double hamon), and kuchigaiba (zigzag).
The blade is abundantly covered with nie, and sunagashi appears.
Boshi is yakitsume with hakikake.

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Answer will be posted at next Appraisal Quiz.

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