Like many gems, amber is used to make jewelry and other decorations. But it s formed unlike any other gem. Amber is actually fossilized tree resin that s 40 million to 60 million years old! Readers learn how this unique gem forms through accessible science content, including fun fact boxes that add even more detail. Close-up photographs of amber in full color engage readers with the fossilization process, the discovery of amber, and what this beautiful, natural gem teaches scientists about Earth s past. Detailed Table of Contents, Fact Boxes, For Further Information Section, Glossary, Index, Graphic Organizers, Full-color photographs.