Previous answer is
Mumei(Unsigned) (Den Shintogo).
無銘(伝 新藤五)

Features: Shintogo Kunimitsu, who lived in Kamakura in Soshu, was also known as Hasebe Kunimitsu and by the Buddhist name Koshin. Judging from the period of his works, this sword is considered to date from the Showa era (1312 CE). This period is especially renowned for the production of outstanding tanto. Among Kunimitsu’s tanto, many suguha works display kinsuji beneath the boshi, and this feature can be observed in most of his works. However, the hamon of Kunimitsu’s works is often very close to the edge, and examples are extremely rare, even among Juyo Token. Generally speaking, Kunimitsu’s tachi are said to be almost nonexistent. Among the examples previously examined, only one signed tachi was known. Swords of this type are therefore considered exceptionally rare. Shintogo Kunimitsu is characterized by producing very few tachi and many tanto. Similar to Masamune, his jigane possesses a clear bluish beauty of the highest quality. The finely forged ko-itame hada is tightly packed, and the lower portion of the suguha appears like softly torn hoshogami paper, creating a truly magnificent work. We highly recommend acquiring this exceptional sword.

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Appraisal Quiz #899 (May 30th, 2026)
Who made this sword do you think ?
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Blade Length: 68.4 cm (26.93 in).
Curvature: 1.3 cm (0.51 in).
Mekugi Hole: 3 holes, 1 of which is filled.
Width at Base (Motohaba): 2.98 cm (1.17 in).
Width at Yokote (Sakihaba): 2.03 cm (0.80 in).
Thickness of rim (Kasane): 0.58 cm (0.23 in).
Sword Weight: 770 g.
Shape: Bohi grooves on both sides extending through the tang to the end.
Jigane: Itame-hada, with a prominent grain pattern and ji-nie, forming a dark-colored steel surface.
Hamon: A soft suguha with a deep nioiguchi, creating a gentle straight temper line.

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Answer will be posted at next Appraisal Quiz.

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