Originally Posted By: wblakey
This post was automatically imported from our archived forum.
Inspected a house today where the copper pipe from the main water shut off, bringing cold water into the house was completely black. It was not powdery, it was evenly distributed and the same age as copper pipe attached to the water heater which was a normal copper colour.
Can anyone tell me what turns copper black? I've seen it go green from corrosion, but never this colour before?