Previous answer is
Mumei (attributed to Den Ayakoji)
無銘(伝 綾小路)

Features:　The Ayakoji school originated from Sadatoshi and included smiths such as Sadayoshi, who were active during the mid-Kamakura period, around the Hoji era (1247–1249).
They resided in Shijo Ayano-Koji, Kyoto, and the smith was known by the Buddhist name Ryoa Beya.
According to sword reference books, Sadatoshi is generally dated to the Bun'ei era, and one theory suggests that he lived near Rai Kuniyuki, with accounts indicating they may have produced swords on each other's behalf.

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Appraisal Quiz #872 (November 8th, 2025)
Who made this sword do you think ?
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Blade Length: 76.6 cm (30.16 in)
Curvature: 2.5 cm (0.98 in)
Mekugi Hole: 2
Width at Base (Motohaba): 3.01 cm (1.18 in)
Width at Tip: 1.78 cm (0.70 in)
Thickness of rim (Kasane): 0.62 cm (0.24 in)
Sword Weight: 855 g
Shape: This blade remains close to its original length, with a deep curvature.
Jigane: The Hamon on the shinogi-ji and that on the main body appear identical.
Hamon: The Hamon is vivid and clear, and the Boshi shows the same characteristics.

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Answer will be posted at next Appraisal Quiz.

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