Some FAQ direct from Dynasty Gallery
How long does it glow?
The length and strength of the glow feature depends on how long the item has been exposed to light, and the intensity of that light.
My item does not glow in the dark. Is it defective?
No, the energy absorbed and emitted (glow) by the items are a natural effect. Each glow in the dark item is made with phosphorus powders fused within the glass. There are certain colors that will make it harder to see the "glow" effect but every piece that is supposed to glow, will glow. Some items may require stronger lights and/or require complete darkness in order to see the glow.