Previous answer is
Mumei (Ko-Mihara)
無銘(古三原)

Features: The width of the blade remains consistent without losing form towards the tip, demonstrating a magnificent and bold creation. Upon close inspection, the suguha hamon is enhanced with fine ashi, and the faint utsuri is apparent. Such a robust work is rare, even for me. It is a highly recommended piece. Ko-Mihara is a smith group from Hiroshima, with works resembling those of Aoe from the neighboring province. The lineage traces back to Masaiye, considered its founder. Although it may appear similar to Aoe at first glance, the visible grain in the jigane and the active hataraki in the hamon reflect a softer touch, leading to its attribution as Ko-Mihara. In any case, this is considered one of the finest masterpieces of Ko-Mihara, showcasing grand workmanship.

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Appraisal Quiz #846 (May 10rd, 2025)
Who made this sword do you think ?
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Blade Length: 70.9 cm (27.91 in)
Curvature: 1.5 cm (0.59 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): 0.7 cm (0.28 in)
Sword Weight: 690 g
Shape:The blade with a wide mihaba and well-proportioned shape.
Jigane:The hada is a mix of itame and mokume, demonstrating well-forged and high-quality jigane.
Hamon:　Ko-nie-based gunome midare with a deep nioiguchi, displaying a soft and elegant pattern. Sunagashi and kinsuji are clearly visible within the ha. The boshi is midare-komi with a double blade (nijuha) at the tip, sweeping in a hakikake style.

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Answer will be posted at next Appraisal Quiz.

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