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Cally Hall

Cally Hall is a geology expert and an author of educational guidebooks that make the subject accessible to a variety of readers. She wrote her first book, a DK Smithsonian Handbook called Gemstones, in 1994. She has also written two science-themed books aimed at younger audiences, Closer Look at Mountains and Closer Look at Forests.
Gemstones

Books

Gemstones

Live Inspired with Compendium: Now Available from PRH!

Exciting news! Compendium has joined the Penguin Random House family, bringing a proven line of bestselling, sentiment-driven gifts to our extensive and ever-growing catalog. Since 1985, Compendium has been creating meaningful moments with beautiful, thoughtfully made gifts that center connection and celebrate occasions both big and small. From greeting cards to inspirational books to impulse-friendly add-ons, Compendium

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