Katana of a top master forging work

Sensei 先生 (master) of the Japanese National Treasure Smith Seiho Sumitani.

Kongō Sai Masatsugu (lived between the Edo period 江戸時代 and Shōwa era 昭和) signed NBTHK attested

with original old Koshirae

Katana blade:

Nagasa: 68,5cm.
Motohaba: 3,15 cm.
Sakihaba: 1,85 cm.
Motogasane: 0,7 cm.
Sakigasane: 0,5 cm.
Nakago hole: One
Hamon 波紋: Suguha and Gunome Midare with Ashi.
Hada: Ko-Itame
Sori: 1,6 cm.
Nakago Mei 署名 (signature): 金剛混正次作 Kongou Sai Masatsugu saku
Signature explanation:
金剛 = Kongou (Kongō) - 混 = Sai
正次 = Masatsugu
作 = Saku = Work (make by)
Age: last years Taishō era 大正時代 / first years Shōwa era 昭和 (antiquity about 100 years old)

This master swordsmith was work during three periods of Japanese History: Meiji era 明治時代 / Taishō era 大正時代 / and the first years Shōwa era 昭和

Kongou (Kongō) Sai Masatsugu was born in the year 1867 died at age of 83 on the year 1950.
He studied under the 2nd generation Munetsugu 宗次 (1) . And is known as swordsmith which deriving from Tairyusai Sokan.
Kongou Sai Masatsugu became a master of the National Treasure Smith called Seiho Sumitani. Seiho (real name was Yoichiro).
Seiho Sumitani received the title of living national treasure in 1981.
He was a student of Sakurai Masayuki 櫻井正幸 (2) , and then separated to do his own work. He greatly admired the Kamakura Bizen swords
The ranking of modern swordsmith of 1942, he was designated as a Saijo Owazamono. Saijo Ô Wazamono (最上大業物, Saijō Ō Wazamono)
This blade is a masterpiece.

Blade condition:
Very good condition, no defects worth mentioning, very slight signs of no importance. The polishing is quite recent and well preserved, it does not need to be done again. The edge is also kept in good condition. This blade does not show any alteration or modification since it was forged.



Wood: Honoki (Hinoki 檜 Japanese Cypress)
Fuchi/Kashira and Menuki couple: Shakudo with Gold inlay
Same: Genuine Ray Skin
Ito: historical black 歴史的な黒人 natural Silk
(this precise natural very deep red tone is another indication of the original age)
A great fine forged iron work with Gold.
Habaki 鎺:
Cooper and Gold a traditional Habaki work.
Wood: Honoki (Hinoki 檜 Japanese Cypress)
Lacquered: Black traditional Urushi
Sageo: Black Silk
Kojiri: black lacquered.

Koshirae condition:
It's an original antique Koshirae from the katana blade times. Perhaps with renewed some something usual.
The general condition is good, showing signs of use and age, but light, as can be seen it through the detailed pictures.



Bukuro 袋 (Katana bag also called because the fonetical translation "Fukuro"):
It is a old craft work quality made of raw silk with gold (textile brocade) in fabric woven a traditional way and themes. Lining of silk fabric.
It is preserved in good condition as can be seen in the pictures.


Original Japanese papers:

Kantei 鑑定 attested blade identification:

Nippon Bijutsu Token Hozon Kyokai (NBTHK) 日本美術刀剣保存協会 Society for Preservation of Japanese Art Swords original Japanese certification of authenticity.

NBTHK Kicho Token paper says this is a 金剛混正次作 Kongou Sai Masatsugu signed Mei Katana. NBTHK Tokubetsu Kicho Token paper issued by this prestigious official organization.


Kyoiku-inkai - Japanese official documentation (paper previously called Daimyo) the document card that testifies to the sword ownership :

Sealed of Prefectural (Kyoiku-inkai) Registration Card In order to legally own a original sword in Japan it has to be registered in accordance with the Ju-to-ho 銃刀法 it is the original card including inscription in equivalent characters of the Katana Nakago Mei (金剛混正次作 Kongou Sai Masatsugu) in order at inequivocal blade identification.

Daimyo Registered: This sword was registered in current sword registration system started in Japan in modern era. Such swords, which were registered in a few years after the system started, are known among collectors as "Daimyo" (feudal lord) registration swords as it was Daimyo or other Daimyo-like wealthy families who owned many precious swords and were asked by the Japanese government to register their swords in the early stage of the newly introduced registration system to familiarize it to the society but it is not the official name of course what is Kyoiku-inkai (Prefectural Registration Card)





Munetsugu (2nd gen)
宗次 / 二代
元治︱ 武蔵
Province: Musashi
Active Period: Started in Genji (元治) era
Father/Teacher: Munetsugu
kuwana-shin koyama kenryushi munetsugu saku
bizen no suke fujiwara munetsugu
kuwana ju nidai munetsugu saku

Masayuki (Sakurai Masayuki)
昭和︱ 福岡県
Province: Fukuoka
Active Period: Shōwa 昭和 era
Father: Masatsugu 正次
sakurai masayuki




Ref.: Katana 127

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