Back to the grindstone today, playing about with these Japanese alloys. Just before I went on holiday, I was having problems with an ochre-coloured deposit on the metals and copper plating: I guessed that this was caused by iron in some way - a hazard in my workshops, where old bits of iron are as likely to be on the bench as precious metals.
Cleaning everything up made a huge difference to the samples and I even achieved some very deep colours on the Shakudo alloy:
The "Polish - Rokusho Only" bag has a strip of Shakudo at the top which is actually deep, deep blue. I'll be trying to achieve that again!
One of the problems is prolonged heating of the solution which has to be done in a glass or copper container and the concentration has to be maintained. Today, I tried using an old slow-cooker to do this and it worked very successfully:
This is Niiro solution, being held at around 60-70 degrees C. The Rokusho needs to be held at almost boiling, which this device does when set on the "high" setting.
Tonight, I am trying a suggestion from James Binion's website and leaving the metal in hot Rokusho overnight to turn the copper deep red. More about that tomorrow.
The skulls from last week are now cleaned up and ready to use:
