Break Open Real Geodes-Ultimate Science Kit provides geodes that are millions of years old and were formed when prehistoric volcanoes erupted. Your child will learn when the geode is broken open that these real geodes offer incredible crystal treasure hidden inside. This ultimate kit includes 15 real geodes from three different mines so your little rock hound can discover and experience a wide variety of crystal formations which could include: Quartz, fluorite, calcite, or even amethyst. Geodes are an amazing natural phenomenon, and cracking them open is a thrill for all ages. This kit also includes safety goggles and a full-color adventure guide filled with information. Geode diameters range from 1.5–2 inches. Your little scientist will find great value in other kits such as the new Glow Rocks Science Kit that offers more properties to discover.