There’s a distinct difference between the appearance of limescale and corrosion. “Limescale is more a chalky, white or off-white deposit, a bit like the stuff you see in a kettle,” explains Ian Wood, ...

I own several apartment buildings, ranging in age from 20 to 50 years old. During the last couple of years they have been plagued by pinhole leaks in the copper plumbing, mostly around the joints.