A20538-Katana: Bizen Kuni Ju Osafune Yozaemon Jo Sukesada.

Katana in Shirasaya(NBTHK Tokubetsu Hozon Token)
Signature: Bizen Kuni Ju Osafune Yozaemon Jo Sukesada.
Eiroku 10 Nen Nagatsu Kichijitsu.
備前国住長船与左衛尉祐定

Fujishiro Toko Jiten:Sue Kotoyo saku: Bizen.
(We divide 4 sections for each sword as Saijyo saku, Jyo-jyo saku Jyo saku
and regular saku)
This sword belongs to Jyo Jyo Saku ranking.
The blade was polished.
Habaki : Gold failed single habaki.
Blade length : 68.8 cm or 27.2 inches.
Sori :2.12 cm or 0.835 inches.
Mekugi : 1
Width at the hamachi : 3.15 cm or 11.24 inches.
Width at the Kissaki : 2.3 cm or 0,9 inches.
Kasane : 0.8 cm or 0.315 inches.
The weight of the sword 820 grams.
Era : Muromachi period Eiroku 10Nen 1568.
Shape : This sword is rather heavy with Ubu style one hole mekugi ana The blade is rather wide and thick with deep sori and long Kissaki nice looking shape.
Jigane :Koitame hada and mokume hada mixed very fine texture and Utsuri appear.
Hamon :Konie deki Gunome midare and cyoji midare mixed with small asha, yo work.
Bo-shi is midarekomi style, and Kinsuji work.

Special feature: Bizen Kuni Osafune Yozaemon Jyo Sukesada is a student of Suemitsu. The Bizen Kuni Osafune Yo so Zaemon Sukesada is very very close so I think These swordsmiths are some relationship.
From Aoi Art: At the end of the Muromachi period, mass-produced Sukesada and carefully produced works and Zokumyo uchi’s work, which was said to be custom-
made, It is roughly divided. This work was ordered by Zokumyo Uchi, and both Jigane and Hamon have been carefully produced.
In addition, this work has a rather heavy weight, and Nakago’s condition is very good, and Yasurime is also firmly visible. It can be said that this work has been carefully preserved
for 450 years with only one nail hole. It is a work that I would like you to cherish and preserve as a family treasure in the future.

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