As the birthstone for May, the emerald, a symbol of rebirth, is believed to grant the owner foresight, good fortune, and youth.
Emerald, derived from the word smaragdus, meaning green in Greek, was mined in Egypt as early as 330 B.C. Today, most of the world’s emeralds are mined in Colombia, Brazil, Afghanistan, and Zambia. The availability of high-quality emerald is limited; consequently, treatments to improve clarity are performed regularly.
- taken from http://www.americangemsociety.org