Grow amazing crystals at home with the National Geographic Glow-in-the-Dark Crystal Lab (Green). The crystal grows in as little as 3 days. Inside is a real fluorite crystal to compare to the home-grown crystal. Seed rock is a glow-in-the-dark element, the crystal itself is white. Place it under sunlight or a strong lamp to get about 1 minute of bright glow. National Geographic’s premium learning guide teaches the fascinating science behind this experiment. Includes 1 crystal-growing powder packet (95 g), 1 glow-in-the-dark seed rock, 1 magnifying glass, 1 wooden spoon, 1 display stand, 1 fluorite specimen and 1 learning guide with instructions. Packaging dimensions are 18.4 cm wide, 25.4 cm high and 6 cm deep. . . . .