Great for: Decorating vases, fish tanks, swimming pools, bars or landscaping. Garden: Get a 300pc glow in the dark garden stones set. Colours: See full list below. Made from: 14mm x 11mm polystyrene resin pieces. Glow in the dark: After being stimulated by sunlight and other visible rays, the product will absorb the energy and naturally glow at night. 300Pc Glow In The Dark Stones | Living Social