EXPLORE CRYSTAL CAVES " Geodes are naturally forming volcanic rocks that contain amazing crystal formations inside. Crack them open and discover beautiful minerals! PREMIUM QUALITY " National Geographic selects only the best geodes collected from multiple mines around the world, so youre guaranteed to find fascinating crystals. INSPIRING A GENERATION " Kids love these treasure-filled rocks! Encourage an appreciation of nature and geology in your child with this extraordinary science kit. TEACHING SCIENCE " Learn all about geodes and minerals with the full-color educational learning guide included.