RG0131CU Copper Vintage Rust Patina Clear LensDESCRIPTION RIGARDS 2021Spring Summer Collection. Half rim frame made of copper, round type eyewear. This is a patina processed model that expresses the ageing process such as fading, wear and rust. The rust treatment (verdigris) is done by adjusting the color by soaking it in a special chemical that has been mixed originally, the soaking time is adjusted by the designer's sense so each item has a different look. Verdigris is a blue green rust