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Artist can't achieve good green patina on Tiffany lampshades?

May 6, 2008

I work with art glass and am trying to achieve a Tiffany-style green patina on copper and/or brass filigree and came metals which surround the glass pieces. I have tried numerous times to achieve this green finish using pre-mixed patina solutions which claim to create a green or blue color on copper, brass, or bronze. However, every time I end up with a black or grayish brown color. Would anyone have any ideas about why I'm getting a black color instead of the claimed green?

I usually prepare the pieces by rinsing them in warm water and scrubbing the metals with Bon Ami and a Scotch-brite pad. I dry them with paper towels and then rub on the patina solution using paper towels. I let the patina sit on the piece for hours, but never get any green coloring, just black.

Do I need to put on more coats of the green patina? Do I need to heat up the metals or solution? Can someone recommend a good pre-mixed patina for creating the green color (or is it better to mix my own chemicals)? Does it look like there's something obviously wrong with my procedure?

Jeff Thompson
artist - Seattle, Washington, USA

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May 8, 2008

Very good green patina for copper and its alloys:300 gms copper nitrate [affil links] /1 lit water,you can brush it on(or spray),after every treatment with this solution paint (or spray )it with 2-3% hydrogen peroxide (you must use synthetic fiber brush,rubber rubber gloves [on eBay or Amazon] and safety goggles [on eBay or Amazon]!).Repeat this process 3 times (at least).Metal must be grease free!Hope it helps and good luck!

Goran Budija
- Cerovski vrh Croatia