A gemstone is a mineral or rock that is sparkling or colourful. Most gemstones are minerals which form in the ground as rock heated in the Earth cools down. As minerals grow, they make regular shapes called crystals. With stunning photographs and easy-to-follow captions, this book explains how different environments affect different gemstones and is full of fabulous, quirky facts such as: although most diamonds are formed underground, sometimes, they fall to Earth from space, inside rocks called meteorites. Gemstones included in the book are agate, amber, amethyst, diamond, emerald, jasper, lapis lazuli, opal, ruby and sapphire. There's a helpful glossary so readers can familiarise themselves with key terms.