Metal sculptures demonstrate varying degrees of UV resistance depending on material composition and protective treatments. Unlike organic materials that degrade under ultraviolet radiation, metals primarily experience surface-level changes when exposed to sunlight. Bronze develops a protective patina that actually shields the underlying metal, while stainless steel maintains its structural integrity through chromium oxide formation.

Modern powder-coated sculptures offer superior UV protection, with advanced formulations resisting fading for 15-20 years. Traditional weathering steel (Corten) intentionally forms a stable rust layer that prevents further corrosion. For optimal longevity, artists recommend: applying automotive-grade wax annually, positioning sculptures in partial shade when possible, and selecting metals with natural UV resistance like aluminum or marine-grade stainless steel.

The interaction between sunlight and metal creates unique aesthetic effects many collectors appreciate. Copper transitions from bright orange to verdigris green, while iron develops rich reddish-brown tones. These natural transformations often enhance the artwork's character without compromising structural stability. For indoor pieces occasionally displayed outdoors, temporary UV-protective sprays can prevent unwanted patina development during sunny exhibitions.