Copper

Copper is a reddish, highly malleable and corrosion-resistant metal long used in architecture for roofing, flashing, gutters and decorative cladding, valued because it forms a stable, protective green patina, a basic copper carbonate called verdigris, when exposed to weather over years or decades. Its use as a roofing material dates back centuries in Europe, visible on many historic church spires and civic domes, and its combination of malleability, allowing it to be formed into complex curved and seamed shapes, with a service life often exceeding a century, has kept it in continuous architectural use through to contemporary cladding on cultural and institutional buildings.