Glow in the dark pendant with special material added to cage pendant and silver plated ring.The handmade glow in the dark material nside brass cage will hold a charge for some hours after being left in the light for a few minutes. It prefers real sunlight or UV light but normal room lighting will cause it to glow as well. Very bright!I use the absolute best glow in the dark pigments on the market. If it isn"t completely amazing... then i don"t sell it! Non radiation, non toxic and etc. Cage diameter is about 10 mm. Glows green & blue. Best glow in full dark on with UV lamp.Each items is handmade and may vary slightly in design.