Crystals, Rocks, and GemstonesA beautifully illustrated, entertaining, and educational guide to the world's crystals, rocks, gemstones, and other geological phenomena from the acclaimed author of What We See in the Stars. Rocks and minerals have captivated the human imagination for centuries. Crystals, Rocks, and Gemstones explores the most interesting and illuminating facts about these precious treasures, from how rocks form and why gems come in different colours, to what makes a