This is a koto Bizen katana.  It looks like its from the  muromachi era. The quality of this sword is good and has no flaws. This blade has been shortened and has bohi that are original to the sword. The hamon is a mixture of gunome/choji midare with an itame/mokume mix for hada that is well forged. The koshirai is black lacquered with Same(rayskin) at the top of the saya. The tsuba is sukashi style. The menuki are round and the tsuki-ito is gold with a sageo to match.  The habaki is gold foiled and very good quality. It is in an older polish with minor scuffing.  It would be a great candidate for shinsa someday.  Its mounted solidly and can even be a good sword for iaido training.

Bizen Province, now the southwest area of Okayama, was once known as the sword kingdom.
Possessing talented swordsmiths and nearby high-quality raw materials accessible by water transportation, Bizen produced the most swords in Japan during the Heian Period (794-1185), beating Yamashiro, Yamato, Sagami and Minohe, the other popular sword-making areas.

In the Muromachi period, Harima, Mimasaka and Bizen province had prospered under the protection of the Akamatsu family. Above all, Bizen province has turned out a great many of talented swordsmiths. Supplying the demand of the Age of Provincial Wars in Japan, a large number of swords were made there in the late Muromachi period. Sukesada has become a synonym for the Osafune School though the founder was Mitsutada. It is regrettable that a deluge devastated the School in Osafune districts in Tensho era. Such is the way of the world that even the Osafune School, that prosperity and power had been unparalleled, perished in this way in the deluge. Old swords are all that is left to tell how once the swordsmiths lived.