Previous answer is
Signature: Mumei (Sengo)
無銘(千子)

Features:　This piece was forged by the Sengo school, known for Muramasa. Features such as matching hamon on both sides and the distinctive “tanago-bara” (fish belly) shape of the tang are characteristic.
Though “Sengo” refers to the group following Muramasa, this particular piece closely resembles the work of the second-generation Muramasa.

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Appraisal Quiz #854 (July 5th, 2025)
Who made this sword do you think ?
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Blade Length: 70.0 cm (27.56 in)
Curvature: 1.2 cm (0.47 in)
Mekugi Hole: 1
Width at Base (Motohaba): 2.94 cm (1.16 in)
Width at Tip (Sakihaba): 2.05 cm (0.81 in)
Thickness of rim (Kasane): 0.64 cm (0.25 in)
Sword Weight: 700 g
Shape: Slightly wide blade with thick kasane, appropriate curvature, and an extended kissaki forming a well-balanced appearance.
Jigane: Finely forged with vivid chikei and a relatively clear utsuri. The shinogi-ji and hira-ji are nearly unified. Although most jigane show masame in the shinogi-ji, here it is itame throughout, forming a remarkable one-piece appearance.
Hamon: A bright and clear suguha hamon with occasional small ashi. The boshi is curved and rounded with visible kinsuji.

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Answer will be posted at next Appraisal Quiz.

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