Previous answer is
Mumei (Katayama Ichimonji)
無銘(片山一文字)

Features:　Katayama Ichimonji is a lineage that prospered after Norifusa of the Fukuoka Ichimonji school relocated to a place called Katayama.
This work features a brilliantly flamboyant hamon, with a refined jigane and vividly prominent midare-utsuri, showcasing outstanding craftsmanship.
As noted by Professor Tanobe in the sayagaki, this piece can be considered top-tier even among the best attributions to Katayama Ichimonji.
Its wide mihaba and large kissaki give it a dignified and powerful appearance, making it an exceptionally attractive sword.

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Appraisal Quiz #850 (June 7th, 2025)
Who made this sword do you think ?
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Blade Length: 2 shaku 4 sun 5.5 rin (approximately 74.2 cm / 29.21 in)
Curvature: 6 sun (approximately 1.82 cm / 0.72 in)
Mekugi Hole: 3
Width at Base (Motohaba): 3.02 cm (1.19 in)
Width at Tip (Sakihaba): 2.12 cm (0.83 in)
Thickness of rim (Kasane): 0.64 cm (0.25 in)
Sword Weight: 745 grams
Shape: Broad blade, thick kasane, deep curvature, and long kissaki.
Jigane: Well-forged ko-itame hada with dense texture. Excellent steel with well-balanced thickness and flawless condition. Hamon is clearly visible on the shinogi-ji.
Hamon: Nie-deki suguha with prominent ko-ashi and visible utsuri. Boshi is round and returns deeply.

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Answer will be posted at next Appraisal Quiz.

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