Once a month
get new photos
and expert tips.

Science and Space
Main Health and Human Body Earth Space Prehistoric World A-Z

Photo Gallery: Gems

PREVIOUS4 of 10NEXT


When the mineral beryl takes on a green form, we know it as an emerald. Highly valued by Mesoamerican cultures, some of the finest emeralds come from Colombia. Beryl is a beryllium-aluminum silicate, and its color comes from small amounts of chromium. Photograph by Peter Arnold, Inc./Alamy

Science and Space