Jim Kelso Posted February 22, 2009 Report Share Posted February 22, 2009 Twenty five years ago or so I started noticing pieces of Japanese metalwork that were either primarily copper or had a copper element that was a very rich red, much deeper red that you usually get with copper in the usual rokusho irotsuke(Japanese traditional soft-metal alloy patination). My earliest enquiry led to a recommendation to heat the piece and get a copper oxide which could then be patinated to a deep red. I tried this half-heartedly, getting mixed results, as I suspected this wasn't really what I was after, as the pieces I had seen were a mix of the usual alloys found in sword fittings, along with the copper, and that was what I really wanted. Heating a piece to get copper oxide would play hell with the rest of the alloys, and I knew there must be some other way. When I met my teacher Toshimasa, this was one of the things I asked about as he had used hiirodo(as he calls it) on one tsuba. He said he used "pure copper" and gave me a piece that had some connection to the Shinkansen or Bullet Train. I tried this but did not get the intense color as seen in his tsuba. I put aside the quest for various reasons until a year or two ago, after seeing a kogo by Shoami Katsuyoshi and asking my friend Murata san, the owner, if he knew how it was patinated. He replied that his friend and mine Katayama san said it is "pure copper" boiled in the usual solution but for ten hours. "Pure copper" is a term that in context can mean many things, as pure is almost always a relative term. I decided that I would try it with a piece of 110 copper alloy(99.9% pure, I think) and another piece of undetermined commercial sheet copper. Both of these pieces came out with very much the same color, after ten hours. I'm attaching the photo of the undetermined, but presumably relatively pure copper. It was photographed in natural daylight and I did nothing to the photo except size it. The red on the thumbtack box is pinkish as it appears. Around the eight hour mark the color started shifting from orangeish to redder. I want to boil one piece for some more time to see what happens. I've compared this color to the Katsuyoshi kogo and on my monitor, they are very close. I wanted to post the Toshimasa tsuba, but my scanner seems putzed. Maybe later. Link to comment Share on other sites More sharing options...
This topic is now archived and is closed to further replies.