CHRWANG Distinctive 1 Bag x 10g Phosphorescent Glow-in-the-Dark Sand Particles 10# Purple This is top of the line glow-in-the-dark, or phosphorescent, pigment Sand Particles , sold by a 10g one bag With an extreme glowing effect this glow in the dark and fluorescent sand can be used in outdoors and indoors decorations also. After it is fully charged in the Sunshine for around 1-2 hours, enjoy the effect in the dark environment! It is also used industrially for safety "EXIT" signs, as seen in many stores today. The powders are made of various rare-earth doped compounds, such as strontium aluminate, calcium aluminate, and zinc sulfide, they are all guaranteed high-quality