Previous answer is
Awataguchi Omi no Kami Tadatsuna
粟田口近江守忠綱

Features: Awataguchi Tadatsuna was a swordsmith active in Osaka during the middle Edo period and belonged to a lineage associated with the prestigious Awataguchi school of Kyoto.
The 2nd-generation Tadatsuna, in particular, became widely known through an incident during the Tenmei era and is regarded as one of the representative Osaka swordsmiths of the 18th century.
Awataguchi Omi no Kami Tadatsuna was also known by the art name Ikkanshi and was highly regarded for his exceptional skill in horimono (decorative blade carvings).
The family claimed descent from Awataguchi Kunitsuna of Kyoto, a renowned swordsmith of the Kamakura period.
His father, the 1st-generation Tadatsuna, moved to Osaka and received the honorary title of Omi no Kami.
The 2nd-generation Tadatsuna is especially famous because of an incident that occurred on March 24, 1784 (Tenmei 4).
On that day, Sano Zenzaemon attacked and killed Tanuma Okitomo, a junior councillor (Wakadoshiyori) and the son of the senior councillor Tanuma Okitsugu, inside Edo Castle.
It is said that the large wakizashi used in the assassination was forged by the 2nd-generation Tadatsuna.

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Appraisal Quiz #920 (October 24th, 2026)
Who made this sword do you think ?
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Blade Length: 69.3 cm (27.28 in).
Curvature: 1.1 cm (0.43 in).
Mekugi Hole: 3.
Width at Base (Motohaba): 2.91 cm (1.15 in).
Width at Yokote: 1.86 cm (0.73 in).
Thickness of rim (Kasane): 0.72 cm (0.28 in).
Sword Weight: 735 g.
Shape: A blade with moderate curvature and a slightly elongated kissaki.
Jigane: Prominent masame hada in the shinogi-ji, while the jigane displays finely forged and tightly packed masame hada with ji-nie.
Hamon: Suguha with a deep nioiguchi, featuring abundant kinsuji and sunagashi.
The boshi is yakitsume.
This is an outstanding blade displaying exceptional activity of the highest quality.

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