Geodes are rocks with a secret. The exterior of the most common geodes is generally limestone or a related rock, but inside is a sparkly quartz crystal or chalcedony deposits. So much fun for geology enthusiasts, rock and mineral collections. A favorite party favor or activity!6x1x3.5" peggable card with information. Part of Copernicus Toys Compact Curiosities line -- small packages full of big wonders. Great little collectible science toys and STEM demonstration items.Perfect for birthday gift bags, party favors, stocking stuffers, and Easter baskets--or any time you need a little science. Spark curiosity for collectors of science and nature.We recommend Compact Curiosities for a wide range of retail settings including toy stores, gift stores, children's museums, science museums, paper and novelty stores.