An exercise for a wet and stormy day

[paulb]

Kantei answer
The sword posted is a wakazashi by the Osaka Ishido smith Yasuhiro.
It is signed Bitchu (no) kami Yasuhiro

 

備中守橘康廣
Bitchu (no) Kami Tachibana Yasuhiro
Explanation:
When first looking at the blade the togari in the hamon and the sunagashi might suggest Mino and an answer to Mino is understandable. However when you look in more detail it leads to a different conclusion
Shape: This is a smallish Ubu wakazashi. The size and shape are typical Kanbun Shinto form.
Jigane the combination of ko-itame and mokume is common to many shinto schools however the description confirms there is midare utsuri. Utsuri is not regularly seen in Shinto work. However the Ishido School specialised in reproducing the characteristics of earlier Bizen blades and utsuri regulalry appears in their blades.
So the shape and hada are leading towards the Ishido School in the Kanbun period. The NBTHK confirm that there is considerable variation within the school and normally an answer to Ishido would be sufficient. However there are other features that can tie this down more closely. The presence of sunagashi and hakikake in the boshi are more common in Osaka Ishido blades. Also the presence of ko-nie in troughs of the choji is typical of the Osaka Ishido work. The hamon combining togari and choji is seen in the work of Tameyasu and one of the most famous Osaka Ishido smiths Nanki Shigekuni. However if it was Shigekuni you would expect to see a midare boshi rather than the ko-maru seen here. Something you might also expect to see is yakidashi starting as a low suguha at the hamachi and rising to the full hamon as it progresses along the blade. It isn’t present here but as Nihonto Koza says “usually but not always”. Once you get to Osaka shinto it really comes down to the mei. Based on the research I did for an earlier paper if I had to choose I would probably have opted for Tameyasu, this smiths father. The hamon is more typical of his style than the examples of Yasuhiro I have found. Fortunately the mei removes any doubt.