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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

Get Inspired! Books for After-School Clubs & Activities

Coordinating after-school clubs and activities in your school community? Explore our collection of books that will help students discover their passion for new (and screen-free!) hobbies. Focusing on topics such as art, board games, crafting, cooking, nature, sports, and more—these books are bound to spark imagination and movement. Browse the middle school and high school

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