copper pipes turned black?

[apcdave]

Hi fellas,

Oil boiler situated in utility room - installed about 4 years ago apparently......quite long runs of copper running up wall into roof space. However all the copper has turned almost black - at first glance I thought somebody had coated it with something but owner says no it has just slowly turned that colour - any thoughts gents?
cheers

dave

 

[Dotty]

Basically it's oxidation caused by the pipework not being lagged. It's a chemical reaction between the oxygen in the water and the copper.

Moisture forms on the pipes, then it dries out. Any oxygen molecules that are in contact with the pipe dissolve, the oxidation occurs and leaves the black patina.

 

[joni os]

Thought missus had brought me a gold ring, but when it turned green realized it was a brass olive.

 

[apcdave]

cheers croppie