Japanese Katana sword, attributed to Toshikazu, with NBTHK certificate - late Edo (19th century).

JAPAN - Late Edo Period (19th century).
Samurai katana.
FUSHI - KASHIRA in silver-plated copper suite decorated with butterflies among plants (symbol of rebirth).
Wooden TSUKA covered with stingray skin, braided with green-tinted leather and decorated with stylized flowers.
MENUKIS in chased and patinated copper featuring a rabbit with spread ears.
TSUBA marugata in iron inlaid with copper threads forming concentric undulations.
SAYA in wood covered with textured black lacquer.
Simple HABAKI in gilded copper.
Straight blade, wide throat, regular, straight and well-marked hamon, tang with three holes, unsigned.
Sold with stand, silk carrying case and NBTHK certificate.
NBTHK also known as Nihon Bijutsu Touken Hozon Kyokai (the Society for the Preservation of the Japanese Art Sword), is one of the oldest Japanese sword evaluation organizations in modern Japan.
Dimensions: 107 x 8 x 8 cm.
Blade length with tang: 89 cm.
Edge length: 69.0 cm.
Curvature (sori): 1.2 cm.
Notes : This blade is attributed to Saiiyounoshin Toshikaz（西條臣俊)，de his real name Yano Toshikazu, in the second year of the Ansei era (1855: at the end of the Edo period). He was an apprentice of Chounsai Tsunatoshi, one of the most famous blacksmiths of the late Edo period.
Toshikazu lived in Yotsuya, Edo (now Tokyo). He also served the Saijyo clan, which ruled part of the lyo domain (today's Ehime prefecture). Saijyounoshin is the name of the title he received, and Yano is his surname.
Tsunatoshi was born in 1798 in the town of Yonezawa, Hashu province (Yamagata prefecture) as the third son of Izumi no Kami Kunihide. His family name was Kato, and he was the younger brother of Kato Tsunahide. Tsunatoshi's real name was Kato Hachiro. Tsunatoshi served the Yonezawa Uesugi clan, a powerful feudal lord in what is now Yamagata Prefecture.
Early in his career, he moved to the city of Edo to learn sword-forging techniques from Suishinshi Masahide, one of the most renowned blacksmiths of the late Edo period.
There is also evidence of him forging swords in Osaka and Kumamoto, while his base was in the town of Azabu in Edo (now Tokyo).
He settled in Edo around 1823 and created most of his work there. He began running his school there, and resided in the Uesugi family home. It is said that he received an allowance from them. He received the honorable title of Chounsai in the first year of the Bunka era (1854).
The school to which Tsunatoshi belonged then flourished in the late Edo period, training many blacksmiths who later became historically important blacksmiths.

Ref: 8ESFA9QT0R