The fact that copper turns green is well known and most everyone has witnessed it in small items, such as bracelets and other pieces of jewelry. But watching a large surface such as a copper roof undergo this process is a sight to behold. As the metal in a copper roof in Indianapolis is exposed to the air, it starts to oxidize. This means that a very thin layer of corrosion will start to form on it. This is called the patina. As time passes, the patina will undergo two main changes: it will become thicker and its color will start to change. The original shiny copper color will transform to green, in some cases turning brown or even turquoise, until eventually, the whole area turns a bright green. The most iconic example of copper turning green at its best is the Statue of Liberty which is covered by the most graceful copper glow.