Order number : 15403
Katana in Shirasaya (NBTHK Hozon paper) (Gassaku Katana : collaborate Tsunatoshi and his son Koretoshi)
Signature : Oite Koufu Chojyusai Tsunatoshi
Chounsai Koretoshi Bunkyu 1 nen 8 gatsu Kichijitsu
(We divide 4 sections for each sword as Saijyo saku, Jyojyo saku Jyo saku and regular saku)
This Chojyusai Tsunatoshi Gassaku sword belongs to Jyo-saku ranking.
Shinshinto : Jyosaku ranking : Musashi province.
The blade was polished.
Habaki : Gold foiled single habaki.
Blade length : 71.0 cm or 27.95 inches.
Sori : 2.0 cm or 0.78 inches.
Mekugi : 3
Width at the hamachi : 3.28 cm or 1.29 inches.
Width at the Kissaki : 2.29 cm or 0.90 inches.
Kasane : 0.72 cm or 0.28 inches.
Era : Late Edo period. Around Bunkyu era. (August Lacky day 1861)
Shape : The blade is wide and thick with suitable sori and long kissaki nice looking shape.
Jitetsu : Koitame had well grained with jinie attach.
Hamon : Niedeki suguha and noter mixed with Kuichigai ha, and small ash double hamon. Boshi is round shape.
Special feature : Chounsai Tsunatoshi the First forged this katana at Edo in 1846.
Born Kato Hachiro in Dewa province, present Yamagata pref.
As the Third son of Izumi (No) Kami Kunihide in 1798, learned under Suishinshi Masahide.
Kato Tsunahide, known as its excellent Toran-ba hamon was Tsunatoshi’s elder brother.
Tsunehide moved to Osaka from Edo and learned under Suzuki Harukuni.
After that Tsunahide went to Kyushu Island and forged sword at Kumamoto.
Around 1823, he lived a house of the Uesugi family at Azabu in Edo.
He passed away in 1863, aged 66.
The sword looks Yamato den style suguha hamon.
It is very rear collaborate Tsunatoshi and his son Koretoshi.
Historical background : Bunkyu Gannen(1st year) Russian battle ship occupied Tsushima Japanese territory.
Bunkyu 2nd January Bakufu chief councilor Ando Nobumasa was attacked by mainly 6 Mito samurai while moving with 50 members of the guards.
He was escaped to the Edo castle with some undergoing trauma and 6 members were killed by the guards.
This picture is the front of the Sakurada mon.(Excerpt from Wikipedia)
NBTHK Hozon paper
Aoi Art estimation paper : whole Oshigata.