Luminous pigment powders can be added into various resin systems, rubbers, and foams to create castings that glow in the dark after being charged with light. The epoxy resin can be filled with luminous powder. Any quantity of powder up to a maximum of 300% by weight can be cast. Note that the luminous powder has the consistency of sand and will settle out of the epoxy. It should therefore be cast in thin layers close to the surface of the part, where it will be exposed to light. It is recommended that tests are carried out in the work place to determine the correct colour and performance required.