Patina on shakudo

Does anyone have experience working with shakudo? I have
alloyed my own sheet, and am finding it impossible to get it to
darken. I have tried a heated ammonia/salt solution as well as a
commercially prepared solution from Reactive Metals, and get
little to no change in the color of the metal. The metal is
pickled, cleaned, abraded, no finger prints… still no color
change once the soluton is applied. I am wondering if some
aspect of my alloying process is preventing it from oxidizing.
Any ideas? Thanks! Karen karen@carvedbyramsey.com

Does anyone have experience working with shakudo?  

I have some experience with 12% and 10% (rem Cu) shakudo. I
gently heated with a soft bushy propane flme to accelerate the
blue/black patina. That’s all. It deepened with the months. Brian

– B r i a n �� A d a m ph/fx +64 9 817 6816 j
e w e l l e r http://www.adam.co.nz a n d
�� e y e w e a r �� m a k e r http://www.adam.co.nz/jewel.htm

Karen,

Shakudo, being an alloy, will develop a ‘scale’ through repeated
heatings (like firescale on sterling). If this scale is not
removed the shakudo will not patina. I’ve found this to be the
case with both Shining Wave Metal’s (4%) and my own alloy (8%).
I generally sand blast the shakudo to make sure all the scale is
removed before I apply apply the ammonia. (Or if I’m going for a
bright finish I buff the daylights out of it with bobbing
compound, then white diamond and finally rouge). When applying
the ammonia (I find Parsons Sudsy Ammonia Detergent works
wonderfully) I run the piece under hot water to warm it, then
dip a soft toothbrush in the ammonia and brush the piece. Hope
this helps…

Susan

Karen, Try some of the traditional recipes for coloring shakudo.
Most involve varying amounts of grated daikon radish; usually
available from a large grocery or an oriental market. Grate the
radish and add it to ammonia, saltwater, or a commercially
prepared solution such as the one from Reactive. I have actually
gotten my best colors using the steam from an ammonia-daikon
’soup’, without actually dipping the piece. Metalsmth