This blade is a beautiful katana by Gassan Sadahide. Sadahide was a student of Gassan Sadayoshi and a contemporary of Gassan Sadakazu. His works are much scarcer that those of his contemporary, Sadakazu. This blade bears the typical characteristics taught to Sadahide by his teacher Gassan Sadayoshi. His given name was Sugimoto Konoshin and his original kuni was Dewa.
This sword bears a sayagaki by Tanobe sensei that reads as follows:
Sesshu Amasaki Ju Unzen-shi Sadahide in a six-character signature and dated Ansei 2 nen (1856). Sword was custom ordered by Konishi Yukiya. Sadahide was a student of Gassan Sadayoshi. This sword has a magnificent appearance because of its shape and dimensions. It exhibits a thick suguha with kinsuji. The deki is highly dignified. Length is 2 shaku 3 sun 8 bu.
Sayagaki signed by Tanzan Hendo (pseudonym or art name of Tanobe Michihiro) in the year of the horse 2014.
The actual signature on the sword is Unzenshi Sadahide Tsukuru. The ura is dated Ansei Ni Nen Ni Gatsu Kichi Nichi (Made on a lucky day in February of 1856). Tame Yukiya Konishi Kun Kitaeru Kore (This was forged for Mr. Yukiya Konishi).
This sword is an excellent example of the Dewa Gassan school. As noted, the nagasa is 72.2 cm or 28 7/16 inches. The moto-haba is 1.3 inches or 3.3 cm and the saki-haba is 0.92 inches or 2.3 cm. It has a shallow tori sori and an extended kissaki. Overall it is a grand sugata as was typical of Sadayoshi and his students. The hamon is a hoso-suguha with a bright nioi guchi that is covered in nie. There is kinsuji and other hataraki within the hamon. The hada is a vibrant mokume and there are areas of what can only be called a form of ayasugi. The nakago is beautifully finished and elegantly signed.
As a footnote it is interesting to know that the person who ordered this blade was a merchant from the Konishi family. Certainly before the waning of the Samurai era no one except a member of the Samurai class could have owned and carried a blade of this length. The Konishi family was well established as merchants who moved from Kyoto to Osaka around this time (Ansei). The Konishi family business began with pharmaceuticals and expanded into alcohol. The family business still exists today. Some of their early buildings have been preserved as historically significant buildings.
This blade is in excellent polish and comes with NBTHK Hozon papers that attest to its quality, the validity of the mei, and condition. If you are a collector of the Gassan school, don’t miss out on this fine blade.