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  for Metal Finishing since 1989
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Oxidizing copper bands

I'm a fashion student, and I'm making an outfit with copper bands. I'm trying to oxidize them, and make them that great verdi gris colour. I've tried lemon juice, vinegar and bleach, but none of them accomplish anything. Does anybody know anything that may work?

Thanks in advance! :)

David Wigley
- Toronto, Ontario, Canada
2002

I am a serious amateur photographer and am looking for the same result - greenish copper finish - for a framing solution. Thank you for forwarding the method.

Tina Mortimer
- Tokyo, Japan
2003

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2003

I don't yet know if this works but while looking for the answer to the same question you both have I came across this. I will try it and I hope I have helped you guys out.

Brushing the copper sheet with a dilute solution of sulfuric acid [H2SO4] will form copper sulphate, the aqua blue tint seen on old copper [due to the action of acid rain].

Use rubber gloves ⇦this on eBay or Amazon [affil links] and eye protection and adult supervision [if necessary].

sulfuric acid is available from automotive supply centers as battery acid ⇦this on eBay or Amazon [affil links] . Start with a dilution of at least five parts water to one acid. ALWAYS ADD THE ACID TO THE WATER WITH STIRRING

NEVER ADD WATER TO CONCENTRATED ACID [it could explode in your face]

Brush the solution on and wait a few moments for results. You'll have to experiment a bit to get the effect you seek.

To stop the coloration, rinse the acid off with a lot of fresh running water.

Felicity Stevenson
- Australia

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Again, is this the same method as natural copper oxidization, which often produces the substance Malachite? Is this the famed patina finish everyone goes gaga over?

Thanks.

Will Thompson
- Holly, Michigan
2005

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Ed. note: You may also wish to read our FAQ about patina finishes.

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2006

Re: oxidizing copper to make it look age


Brushing the copper sheet with a dilute solution of sulfuric acid [H2SO4] will
form copper sulphate, the aqua blue tint seen on old copper [due to the action
of acid rain].

Use gloves and eye protection and adult supervision [if necessary].

sulfuric acid is available from automotive supply centers as battery acid ⇦this on eBay or Amazon [affil links] .
Start with a dilution of at least five parts water to one acid.

ALWAYS ADD THE ACID TO THE WATER WITH STIRRING

NEVER ADD WATER TO CONCENTRATED ACID [it could explode in your face]

Brush the solution on and wait a few moments for results. You'll have to
experiment a bit to get the effect you seek.

To stop the coloration, rinse the acid off with a lot of fresh running water.

Dawn Butz
- Tucson, Arizona, USA