Previous answer is
Mumei (Attributed to Den Rai Kunitsugu)
無銘(伝 来国次)

Features: Rai Kunitsugu was a Yamashiro school smith.
His hamon is characterized by straight-line choji-midare, with active ko-ashi and well-defined utsuri. The boshi returns round and slightly long.

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Appraisal Quiz #851 (June 14th, 2025)
Who made this sword do you think ?
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Blade Length: 2 shaku 3 sun 4 bu (71.0 cm / 27.95 in)
Curvature: Just over 4 bu (1.21 cm / 0.48 in)
Mekugi Hole: 3
Width at Base (Motohaba): 3.37 cm (1.33 in)
Width at Tip (Sakihaba): 2.12 cm (0.83 in)
Thickness (Kasane): 0.73 cm (0.29 in)
Sword Weight: 870 g
Shape: It is nearly ubu (unshortened), with a wide mihaba that remains consistent to the tip (2.12 cm), and a deep curvature, making it a magnificent work.
It has a thick kasane and is excellently crafted.
Because it has a shinogi-ji, the forging of the shinogi-ji can be clearly observed.
Jigane: Ko-itame hada, densely forged with well-visible utsuri.
Hamon: Nie-based suguha with active ko-ashi, the boshi is rounded and slightly turns back.

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Answer will be posted at next Appraisal Quiz.

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