Katana signed Bungo-koku Kutami-gou Ju-nin NORISADA-saku In the 15th day, the 2nd month of Houtoku 3rd

Koto Early Muromachi period (Houtoku 3/1451) Bungo
Length of cutting edge 77.0cm Curvature 1.95cm Width of base 31.5mm Width of Yokote 20.0mm Thickness of base 8.5mm

NBTHK(Tokubetsu Hozon) certificate

Reported in Kozan Oshigata

Sugata(configuration) : Long Katana of Shinogi-zukuri with Iori-mune and high Shinogi-suji ridge configuration in a gallant manner, the blade is wide in Mihaba, abundant Hiraniku and waist point curvature while the upper rest is nearly straight that leads to an elongated middle tip of Kissaki. This configuration created in heroic style is designed as horseback battle for thrust rather than cut. (click HERE for higher resolution image)
Kitae(forging pattern) : The excellent choice of fine steel gives off bluish tendency. Kitae is based on conspicuous streaming Itame hada generally with an indication of Masame tendency. Sparkling frosty Ji-nie is distributed over the Hira-ji surface and bluish gleaming lines of Chikei layer lilvely wells out from steel in different carbon content.
Hamon(tempering pattern) : Hamon state is rather on harder, stronger side, uniform dense "Nie-deki", Suguha with shallow undulating Notare, combined with minute Ko-Midare tendency where frequent short line feet of Ko-Ashi radiates on cutting edge. Boundary line consists of apparent Hotsure flay or clear Niju-ha double lines in places. In the interior of temper is filled with dense misty Nioi where abundant floating YOU appears. Entire quenching scene is full of abundant flashing Nie and deep Nioi activities where gives off the most brilliance.
Boshi (tip): Wide and strong in temper to form Kaen that burst into flames that ends almost no-return called Yakizume.
Nakago(tang) : UBU original. There is a warp in Nakago to form Koshizori curvature. Two original large Mekugi-ana retaining holes. Shallow slanting left "Katte-sagari" filemarks and flat back ridge forms shallow "Katte-sagari" filemarks. The entire Nakago preserves excellent taste of patina in 570 years. The classically large chiseled long character inscription that starts from the place of work Bungo-koku Kutami-gou Ju-nin 豊後國朽網郷住人 and smith name NORISADA-saku 則貞作.
The other side inscription is the date of year In the 15th day, the 2nd month of Houtoku 3rd (1451) 于時宝徳三季二月十五日

Town of
Kutami, Bungo domain is now Nagayu, Naoiri-cho Takeda-city, Oita-pref., TAKEDA 竹田城 castle town under patronage of a general Shiga 志賀氏 who was a vassal of feural lord of Otomo clan 大友一族.
In Bungo province a scared mountain Ehiko-san 英彦山, a Buddhist priest sword smith SADAHIDE 定秀 (1205-) who belonged to Senjuin 千手院 emerged then a successor YUKIHIRA 行平 who enlisted Emperor Go-Toba's 後鳥羽天皇 monthly service created highly defined archaic style. In the period of the Northern and Southen Dynasties (1329-89), Ryokai 了戒escaped from Kyoto to establish Yamashiro tradition.
The subject Katana is quite rare dataed in the 15th day, the 2nd month, Houtoku 3rd (1451). Exceedingly long Katana that has curve near the base while the rest is nearly straight. This configuration was designed for horseback battle.
It's workmanship features typical Yamato tradition that reminds one of Senjuin 千手院 school.
Abundant Hiraniku remains, impressively heavy on hand, Nakago holds an excellent taste of patina in 570 years where remains clear chiselled long inscription in classical grace as well as the date with year 1451 of great historical value.This Katana has been treasured by Naito 内藤家 families in generations of the Koromo 挙母 domain (now in Toyota-city)
Gold foiled double layers Habaki collar, Preserved in Shirasaya plain wood mounting
Recent polish/Condition scale: mint - excellent (using a scale of mint-excellent-very good-good-fair-poor)
reference data :
HNMA KUNZAN, Nihonto Meikan, Yuzankaku, 1975