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 .

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 . See less