Tanto in Shirasaya(NBTHK Tokubetsu Hozon Token)
Signature: Mumei(judged as Yamamura Yasunobu)
Middle Koto: Jyo saku:Echigo.
(We divide 4 sections for each sword as Saijyo saku, Jyojyo saku Jyo saku and regular saku)
This sword belongs to Jyo jyo saku ranking.
habaki: Gold foiled single habaki.
The blade was polished.
Blade length : 25.0 cm or 9.84 inches.
Sori : 0.0cm or 0.0 inches.
Mekugi : 1
Width at the hamachi : 2.45cm or 0.96 inches.
Kasane :0.47 cm or 0.18 inches.
The weight of the sword :145 grams
Era : Late Nanbokucho period to Muromachi(Ouei era) period.
Shape : Uchizori, Mitsumune style Tanto.
There are Hi and Gomabashi engraving on the blade.
Jigane : Ko Itame Hada well grained with Jinie attach. There are Utsuri.
Hamon : Ko Nie Deki, Gunome Midare with thick Nioikuchi. And also Notare Hamon. Boshi is round shape.
Special feature: Yamamura Yasunobu was a student of Nobukuni(Kyoto, the first generation). They made swords for Samurai from generation to generation. At a glance, the blade is similar to Rai school. Suiken’s Sayagaki said that the blade is Rai Kunimitsu. Suiken is the author of a famous book called Encyclopedia of Japanese Swords. It is diffucult to say whether Rai Kunimitsu is correct or Yamamura Yasunobu is correct, but I feel that Nobukuni school is different.
From Aoi Art: According to the Sayagaki, Suiken said that the blade is Rai Kunimitsu. But NBTHK judged the blade as Yamakura Yasunobu. Suiken published the Encyclopedia of Japanese Swords, and we use that book. I feel that it is a little unreasonable for Yamamura Yasunobu. The Jigane is very good and Hamon is also elegant. In general, the Yamamura school has many Suguha Hamon. Yamamura Yasunobu was the lord of a castle and also made swords. His master was Nobukuni. Therefore, he calls himself Nobukuni.
NBTHK Tokubetsu Hozon Token.
Aoi Art estimation paper: whole Oshigata by Ayaka Tsuruta