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Blackening of brass and copper at room temp

I want to know how to blacken brass and copper at room temp, blackening of iron and steel and also green patina on brass.

Vineet Lohiya
SURFACTANT INDUSTRIES - JODHPUR, RAJASTHAN, India
2002

See letter 36214.

Dan Brewer
chemical process supplier - Gurnee, Illinois
2002

2003

Black for copper and brass:

200 gm copper carbonate ⇦ on eBay or Amazon [affil link]

1 lit ammonia ⇦ on eBay or Amazon [affil link] 25% Cold immersion!Work outside or you need strong ventilation!1-4 min.

Green for brass:

200 gm copper chloride

100 gm potassium chloride

1 lit water Black for iron and steel:

20 gm tannic acid ⇦ on eBay or Amazon [affil link]

20 gm tartaric acid ⇦ on eBay or Amazon [affil link]

1 lit water Only grease and oxide free objects can be coloured!

Goran Budija
- Zagreb,Croatia

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