Add these powdered metallic paints to distilled water or acrylic medium, or mix them with any water-based paints for a wide range of lustrous effects. Extremely brilliant, opaque and absolutely lightfast, they're versatile additions to any artist's materials. Our Tarnish Resistant Palegold and Richgold are made from bronze powders chemically bonded with a silica coating which resists the natural aging effects of humidity. Our original metallic watercolors are made from genuine metal powders—microscopically flaked particles of copper, zinc and aluminum. While they are all specially coated to delay the tarnishing effects of air and moisture, the Tarnish Resistant powders go one step further and remain virtually unchanged. The powders are mixed with a neutral pH binder that activates with water. The original metallics gain a slight patina over time and darken from exposure to moisture in the air when used as a watercolor. If this natural aging or tarnishing is a concern, we suggest finishing your pieces with Daniel Smith Picture Varnish, or framing with glass or plastic to protect them from the atmosphere.