Cally Hall is a geology expert and an author of educational guidebooks that make the subject accessible to a variety of readers. In addition to DK Handbook: Gemstones, she has also written science-themed books aimed at younger audiences.

Unearth a treasure trove of knowledge of over 130 gemstones from around the world. Learn how gemstones are formed and how to recognise them by their unique qualities and colours. A wonderful book for beginners, students, and gemstone-enthusiasts that includes the latest scientific research and gemstone classification. Gemstones is filled with all you need to know about these fascinating minerals - cut and uncut stones, organic gemstones, and precious metals. Inside you'll find: - Fast facts for quick reference, including chemical composition, hardness, gravity, lustre, and reflective value- Photo close-ups of key details and highlights of distinguishing features- Illustrations of faceting and shapes popular for each gemstone- A detailed introduction to everything a beginner gemologist needs to know including how gemstones form, the different properties, crystal shapes, faceting, and the history of gemsDelve into the one-of-a-kind characteristics, colours, and attributes of more than 130 gemstones with this compact visual guide. For easy classification, each stone's entry includes annotated photographs to highlight distinguishing features and concise details about the attributes of gems. Designed for beginners and experienced collectors alike, this gemology book explores what gemstones are, how they are classified, and how to identify them by their physical and optical properties. It also shows you how they were fashioned and imitated throughout history. Learn the differences between varieties of cut and uncut stones, organic gemstones, and precious metals. It includes a glossary for many more technical and scientific terms and over 800 high-quality photos of gems. It's the ideal gift for any budding gemologistThe DK Handbook series is an incredible collection of titles that fascinate curious minds. Other books include Rocks and Minerals, Dinosaurs, and Prehistoric Life, and Stars and Planets.