Here's another ring I did with a permanent oxidized patina. The metal is 14K yellow with a platinum bezel. I make the alloy part myself with 50-50 silver and copper. Commercial alloys don't work at all or barely. This homemade alloy can be easily contaminated by melting in crucibles previously used for commercial alloys so crucibles must be fee of other metals. I use a weak (2 grams sulfur to 8 oz. H2O) liver of sulfur solution and boil for a couple hours. The metal comes out shiny and still polished but darkened with blue, red and purple tones reminiscent of a burned chrome Harley muffler. You can ultrasonic and steam the finish, even throw it in the pickle and it stays on. Soldering and hot flux will remove the finish though so I'll have to insulate well if I resize this for a customer later. I made this for stock with a fine .88 carat tsavorite garnet flanked by two .05 ct. yellow diamonds. I engraved a "dead branch with spiral" motif on the sides.
Here's the ring before I polished the highlights and set the center stone which could be damaged by the sulfur solution.
