Using the experience of several years of research and development, UGIEL takes advantage of the outstanding properties of gold and silver to give their pigments a wide range of colourful appearances and functionalities. UGIEL’s patented technology consists in coating individual micrometric support particles with self-organized gold or silver layer with a resolution of about ten nanometers. By controlling microstructural features of this layer and the amount of deposited precious metal, we are able to tune the obtained colours and specific colour effects.