Previous answer is
Mumei (Unsigned, attributed to Awataguchi)
無銘(粟田口)

Features: This tachi is attributed to Awataguchi Hisakuni, a highly regarded smith of the late Heian Period.
Its ubu nakago, single mekugi hole, and remarkable condition make it an extremely rare and valuable piece.
The absence of bo-hi allows a clear view of the jigane, making it an exemplary artifact for study.

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Appraisal Quiz #824 (December 7th, 2024)
Who made this sword do you think ?
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Blade Length: 69.5 cm (27.36 in).
Curvature: 2.8 cm (1.10 in).
Mekugi Holes: 3.
Width at Base (Motohaba): 0.91 cm (0.36 in).
Width at Tip (Sakihaba): 2.02 cm (0.80 in).
Thickness of Rim (Kasane): 0.66 cm (0.26 in).
Sword Weight: 610 g.
Shape: Slightly wider blade with deep Sori.
Jigane: Tight Koitame grain with a well-forged surface, showing utsuri (shadow patterns).
Hamon: Nioi-based, fine gunome midare (irregular wavy pattern), mixed with reverse irregularities.
The boshi (tip hamon) exhibits the style of Mitsuyasu.
The beautiful jigane and remarkable hamon featuring reverse choji midare (clove pattern).

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Answer will be posted at next Appraisal Quiz.

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