100-Pieces: Glow in the Dark Luminous StonesGlow in the dark pebbles mark a path or highlight a flower bed. 100 piece set Line a walkway, edge a flower bed or fill a planter with these unique acrylic pebbles. After being exposed to daylight, these pebbles glow in the dark. Glow lasts approximately two to three hours after full sun exposure. These are a flat marble size and are made of a poly resin material. Features: Uses: vases, aquariums; gardening, swimming pool and decoration of bars; Villa