I like coming across these early kinko guards that look like they may have been the inspiration for Hirata Hikozo’s work. The color of the alloy combined with the lacquer along with the fukurin and carving have much the same flavor although Hikozo refined them all and built on it.
I had always thought the tagane were also original to these pieces, but a friend pointed out that they may have been added as an upgrade toward Hikozo’s tagane mei. It’s certainly possible, but I also see them on guards around the same age that I think would really take some imagination to try to pass off as Higo. For example:
They’re also seen on some iron Saotome tsuba, but the rest of the work is quite different, so probably no direct connection.
Setting Hikozo aside, note that the surface of this one is not covered with nanako or even worked with a ring-shaped punch. Each circle is made up of a series of tiny punch marks. I wonder if this was a country guy’s imitation of nanako or something original and maybe earlier.
In this case the fukurin is needed to finish the three layer construction of the plate. Unlike the typical san mai guard, the shakudo here is only a thin foil. There is (of course) a specific term for this that I’ve forgotten. A microscope view inside the kozuka ana is here:
It appears to be quite a tight bond without signs of solder. I don’t know how it was done. Yes, I labeled the photo incorrectly way back when, it really is the inside of the kozuka ana.
Tsuba Kansho 