What Are Rocks Made Of? (Rock-ology: The Hard Facts About Rocks)

A chunk of granite rock may look grey and boring, but take a closer look under a microscope and it's possible to see that the rock is made from billions of tiny colourful grains. Each microscopic grain is a substance called a mineral, and it's minerals that are the ingredients that make up all the rocks on Earth. In this book, readers will learn how different combinations of minerals create different types of rocks. They'll discover that metals, such as gold, are actually minerals that can be found in rocks. And they'll learn that some minerals grow as beautiful shapes called crystals that can be made into precious gemstones such as rubies and sapphires.