Interference fluid colors offer a unique "interference flip" when viewed from different perspectives. They flip between a bright opalescent color and its opalescent complement when applied over white surfaces. Over darker surfaces, the bright opalescent color is very noticeable, but the effect is not evident. They can be combined with small amounts of color to achieve unique color ranges. They can be mixed with gels for impasto effects or thin with mediums for glazing applications. When a very small amount of black is added to Interference colors they produce deeper, richer, opalescent effects.