AS21373-Tanto: Bizen Koku Ju Osafune Magouemon Jo Kiyomitsu

Tanto in Shirasaya (NBTHK Hozon Token)
Signature :　Bizen Koku Ju Osafune Magouemon Jo Kiyomitsu
備前国住長船孫右衛門尉清光

(We divide 4 sections for each sword as Saijyo saku, Jyo-jyo saku Jyo saku and regular saku)
This sword belongs to Jyo saku ranking.

The blade was polished.
Habaki : single foiled gold Habaki
Blade length :　24.54cm or 9.66inches.
Sori :0cm or 0inches.(Takenoko)
Mekugi : 1
Width at the hamachi : 2.48 cm or 0.97inches.
Kasane : 0.78 cm or 0.30 inches.
The weight of the sword: 210 grams.
Era : Late Muromachi period, Genki era.
Shape: The blade is slightly wide, thick and looks solid.
Jigane: Itame hada well grained with jinie attach, Chikei and Utsuri appear.
Hamon: Nie deki Suguha Hamon, there are slightly deep Nioikuchi and soft Koasi. Boshi is Midare Komi style from near the Monouchi and turns back sharply.

Special Feature: From the early Muromachi period, people called the sword smiths from Bizen Osafune and their swords as “Suebizen” from their characteristics. Many swordsmiths refer to themselves as Suebizen, but it is said that Gorouzaemon and Magouemon Kiyomitsu were the best smiths in the Suebizen group. Magouemon was great at making Suguha.
There are some Kitae Ware(forged cracks) and small nicks near the Kissaki part.

From Aoi Art: There are Suebizen works with Zokumyo(the real name of the swordsmith which was sometimes engraved on Mei when the work was so great made and they feel proud about the work) and without which was mass-produced. This work has a Zokumyo and is supposed to be made-to-order. For a Magouemon this sword is relatively firm and has a thick blade.

NBTHK Hozon Token
Aoi Art estimation paper: whole Oshigata.