Ordering number: 19483
Katana(Nagamaki Naoshi) in Shirasaya(NBTHK Hozon Token)
Signature: Mumei ( Ko-Naminohira)
(We divide 4 sections for each sword as Saijyo saku, Jyojyo saku Jyo saku and regular saku)
This sword belongs to Jyo saku ranking.
The blade was polished.
Habaki :silver single habaki.
Blade length :64.9cm or 25.55 inches.
Sori :2.0cm or 0.787 inches.
Width at the hamachi: 2.825cm or 1.112 inches.
Kasane:0.64 cm or0.252 inches.
Weight of the blade: 485 grams
Era : Late Kamakura period 1330.
Shape: At that period, This Nagamaki is very long and keeping the style.
At later on, the nakago was cut shortened.
But still keeping good condition.
Jigane: On the black colored jigane, itemehada,
Oo item(big item) hada and also mokume hada mixed
visible to see the texture well and also small chikei and Utsuri appear lightly.
Shinogi Ji is as same as Hiraji item and oo itame hada.
Hamon: Nie deki suguha moisten like morning mist
and can see sunagashi and many kinsuji in Hamon.
Special feature: The sword Ko-Naminohira is old Naminohira used limitedly the swordsmiths and their swords of Naminohira School at the end of the Kamakura period. It is said that the First Masakuni was the founder of
Naminohira School in Satsuma province. He moved from Yamato province
and decided to live permanently at Naminohira where had produced good quality iron sand and charcoal indispensable to forge the sword. On the way of went back to meet his wife and children, Masakuni caught in a storm. Soon after he throws an elaborate sword overboard to dedicate, the stome abated and he had a narrow escape. This episode may be only legend but has had a wide influence down the ages to own Naminohira sword refusing disaster at sea.
Yukiyasu, Yasuyuki, Yasumitsu and Yasutsuna were representative swordsmiths.
From Aoi Art: This sword is deep sori and wide shinogiji and Mune is very sharp. Nakago thickness is just only ０．４６cm.
Probably sword smith considered to make the lighter weight of the blade.
The blade has passed about 690 years has passed and still can see the blade as Kansyo（appreciation)as JIgane and Hamon well.
NBTHK Hozon Token
Aoi Art estimation paper: whole Oshigata.