AS18474 Katana:Nagasone Okisato Nyūdō (partially cut) Kotetsu(NBTHK Hozon Paper)

Ordering number:AS18474

Katana in Shirasaya (NBTHK Hozon Paper)

Signature :Nagasone Okisato Nyūdō (partially cut) Kotetsu
長曽祢興里入道（以下切れ）虎徹
　　　　
Shinto:Saijyo-saku:Saijyo oowazamono cutting test ranking.
(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.
The blade was polished.
Habaki :silver single habaki.
Blade length :　65.4　cm or 25.74 inches.
Sori :1.2cm or 0.47 inches.
Mekugi : 　4
Width at the hamachi : 2.90 cm or 1.14 inches.
Width at the Kissaki : 1.83cm or 0.72 inches.
Kasane : 0.58cm or 0.22 inches.
Sword Weight: 550 g
Era : Edo period Kanbun era.
Shape : The blade is about 5cm Suriage and Machiokuri.
The blade is regular width, thickness
with small sori and regular kissaki Kanbun shape.
Jigane :Koitame hada well grained with jinie attach beautiful top quality jigane.
Hamon :Niedeki suguha notare with asi and sunagashi, small kinsuji work.
Boshi is notare round shape.

Special feature:Nagasone Kotetu was working at Echizen prrovince for
making Yoroi and Kabuto. his made Kabuto is very strong
and well grained jigane and achieved high evaluation. But after the
war end, it is very hard to make continue hiss business, so he moved
to Edo and decided to make swords at age 50. He was called Sano no
jyo and named Kotetsu Japanese Kanji 古鉄　old iron)From Meireki 2nd
to Enpo era, he named Kotetsu.
His sword is quite well grained jigane and bright round shape gunome
midare hamon which is called Jyuzu ba. In his subjects,
the most highest ranking swords are Nagasone Okisato signature.

From Aoi Bijyutsu: Nagasono Kotetsu started old age for making swords so his swords are very few at present. Many swords collectors aspire his sword.Special feature of Kotetu is beautiful Jigane and bright and clear hamon (akaruku saeru in Japanese) At many yeaars ago I saw Kotetsu at London’s Auction the blade is cutting test on the back and bright beautiful jigane even right now I remember.
As you know Kondo Isamu chief of the Shinsengumi loved Kotetsu cuto well sword. It is a mystery why his sword is sharp even thou his starting making sword is 50 years of age.
Probably his previous work making Kabuto helped a lot I think.

NBTHK Hozon paper.
Aoi Art estimation paper:　whole Oshigata.