That blue-green crust on old copper roofs is not dirt. It's patina, and it shields the metal for centuries. The Statue of Liberty took about three decades to turn from brown to green.
61 reposts437 likes
That blue-green crust on old copper roofs is not dirt. It's patina, and it shields the metal for centuries. The Statue of Liberty took about three decades to turn from brown to green.
61 reposts437 likes