About the change in color of copper sheeting (About patina)
Copper sheeting is often used as roofing material and decoration metal for Japanese-style architecture. When Copper is exposed to rain and wind for a few weeks, it will change in color to brown and then over time develop a patina on the surface. Copper has its value because of the process of changing color. Patina can add value effectively. It works by coating the surface so it can prevent the copper sheeting from corrosion or bacteria. Please enjoy watching it change its color.