This is a blade by Sukesada and it is dated as being made in August of the fourth year of Genki (1573). The Sukesada smiths of the Bizen school were one of the most prolific groups of smiths. They worked from the early Muromachi Era throughout the Muromachi and Edo Eras. There were smiths by this name forging swords right up until the Meiji restoration of the later part of the 19thcentury. There were probably over a hundred smiths who forged using the name Sukesada throughout Japanese sword history.
This katana was forged toward the end of the Muromachi Era when the style of forging changed from the making of the uchi-gatana that possessed a short nakago for one-hand use went out of vogue. At this time there was a return to longer swords of 70 cm or more that were used with the traditional two-handed grip.
This sword is signed on the omote, Bishu Osafune Sukesada (備州長船祐定). It is dated on the ura, Genki yon nen hachi gatsu (元亀四年八月)(made in August of 1573). It is o-suriage but it retains its signature which is now located at the bottom of the nakago. It has a cutting edge length of 69.5 cm or 27.56 inches. The moto-haba is 3.1 cm or 1.21 inches and the saki-haba is 2.35 cm or 0.93 inches. The Kasane is 0.76 cm or 0.3 inches and the sori is 1.42 cm or 0.56 inches. The sori is a mild koshi-zori due to the shortening of the blade. There is a feint utsuri on both sides of the blade.
The hamon is a mixing in of gunome-choji-midare which is called “kani-no-tsume” (crab claw), peaked gunome choji, and even areas of tadpole choji. There a very bright and tight nioi-guchi. The bôshi is almost ichimai (full temper) with a short kaeri.
This blade is in good sashikomi polish with a few scratches here and there. There are no problems or flaws. It comes in a shirasaya and has an old gold washed habaki. It is accompanied by NBTHK Hozon Tôken papers attesting to the validity of the signature and the quality of the blade.