Blackened copper pipes

Is anybody familiar with why copper pipes are solid black IMG_2711.JPG

Try here .

Black copper cold water lines- InterNACHI Inspection Forum](]( › …› Specific Inspection Topics › Plumbing Inspections

thanks Roy

If the cold lines are black and hot lines are not so black condensation has been one of the factors. Very common where I am, and nothing to get excited about, there has been no chinese drywall or any of that where I am, but I am in oil country, lots of oil and gas wells, refineries and gas plants all around, so I am thinking that is also a factor. I take it more as an indication that they need to do something about excess humidity in the basement in summer than any problems with the water lines.