The fluorescent pigments are divided into PHOSPHORESCENT - meaning pigments that contain phosphorus and are brighter with more vibrant colors, and FLUORESCENT - which emit light and glow by themselves in the dark. This is a line of powders from VAN d'EYCK consisting of 11 phosphorescent powders with uniquely vivid shades ideal for mixing with any base you desire. They are pure high-quality pigments and very fine powder particles that dissolve immediately without much effort in the mixing process.