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Oxidize copper using Cuprous oxide red to get red color

Hi,

I am a craftsman and need to oxidizer copper to permanent red color. I have been using copper oxide black for black color oxidization but now need to have red oxidization color for my arts. I was told of the cuprous oxide red. Used it with not diluted hydrochloric acid. But the color is not perfect. Please let me know if there are any suggestions on how should I do it. Thank you.

JK Shakya
Craftsman - Nepal
May 12, 2011

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May 17, 2011

Try next solution : 25 gms copper sulphate/ 1 lit water.Immerse your object in boiling solution,then after 15 minutes add 0,5 gm ammonium chloride and continue boiling for next 10 minutes.According to Hughes,Rowe: The Colouring, Bronzing and Patination of Metals, London 1997.
You can find some other recipes for red colouring of copper in my download free booklet on metals colouring and plating: (http://attachments.wetpaintserv.us/ZLSnLKosv0l3CnE9hGDi7w488720)

Hope it helps and good luck!

Goran Budija
- Cerovski vrh Croatia

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Ed. note : Thanks, Goran. Terrific booklet!

Ed. note Jan 2017: Although wetpaintserv.us was a legitimate site when Goran posted this, it is currently a malware site. DON'T GO THERE!! Goran has been kind enough to upload his booklet to https://www.finishing.com/library/budija/budija.pdf.