Copper turned a gunmetal color
by Karen
Hi stacy,
I made copper bangle bracelets. They were patinated in liver of sulfur. I then experimented with brass brushing some of the bracelets instead of using a 3M pad or steel wool. When they came out of the tumbler, after 3+ hours, some of the components looked more silver than copper. It was an interesting patina, but not what i wanted this time.
Could you please explain a bit more about the effects of brass brushing on copper. Is there anything i can do to change this silver gunmetal color?
Thanks so much.
Karen
Stacy's Answer:
Hi Karen,
I don't use a brass brush on copper mostly due to the fact that I don't want to have that sort of texture on my metal that the bristles can sometimes leave. So as to any "reactions" between the two metals, I'm unaware of any. I've had no problems combining brass (a copper alloy) and copper together with or w/out silver in designs while soldering, polishing, tumbling, etc.
My liver-of-sulfur patinas on copper often come out of the tumbler looking like gunmetal. I simply polish using a jewelry polishing cloth, Sunshine brand by Rio Grande to be specific because I like how they work on copper. The excess patina is removed, exposing a bright copper finish on the higher areas of the design or where I buff with the Sunshine cloth. You can also scrub using a 3M soft scrubbie or fine steel wool for a brushed finish also exposing a lighter copper color in the brushed areas where you've removed the patina.
Copper being copper, it will contine to oxidize even after a patina such as LOS has been applied. Simply enjoy the changes or buff with a polishing cloth to restore shine and a brighter copper color to the metal. Steel wool or a fine/soft brass brush will give the metal a brushed texture finish.
