Artists harness the natural processes of time and decay to infuse metal sculptures with depth, meaning, and a sense of evolution. By intentionally exposing metals like iron, copper, or steel to environmental factors, they create works that change visually and conceptually over time.

Oxidation is a primary tool, with rust forming intricate patterns on iron sculptures. Artists may accelerate this process chemically or let nature take its course, embracing unpredictability. Copper develops a verdigris patina, adding rich greens and blues that evolve with exposure. Some sculptors even incorporate organic materials that decay at different rates, creating contrast between permanence and transience.

Thematically, these techniques allow commentary on mortality, environmental change, or the passage of history. Modern artists often combine aged metal with polished elements to represent duality. Others use decay to challenge traditional notions of sculpture as static, instead creating living artworks that transform through their lifespan.

Technical approaches vary from controlled patination using acids to uncontrolled weathering installations. The resulting textures and color shifts add tactile and visual complexity impossible to achieve through artificial finishes alone. This embrace of impermanence makes each sculpture uniquely responsive to its environment and viewers' perception of time's relentless march.