A brittle gem which has a tendency to chip and is rarely flawless: The rich green color of emeralds are caused by the presence of chromium, a hard white metal.

In ancient times, powdered emeralds were believed to cure fever and the plague.

Emeralds are formed from a combination of three main minerals: silicon (the chief constituent of sand and quartz), aluminum, and beryllium.

Colombia is the source of the finest emeralds.