Emerald is the bluish green to green variety of beryl, a mineral species that includes aquamarine.
The most valued variety of beryl, emerald was once cherished by Spanish conquistadors, Inca kings, Moguls, and pharaohs. Today, fine gems come from Africa, South America, and Central Asia.
Gem experts differ on the degree of green that makes one stone an emerald and another stone a less-expensive green beryl. Most gemologists, gemological laboratories, and colored stone dealers call a stone green beryl when its color is "too light" for it to be classified as emerald. Even among that group, however, there's a difference of opinion about what's considered "too light."
Age of the oldest emeralds, from South Africa.
2011 sales price for Elizabeth Taylor's emerald pendant - a record $280,000 per carat.
Pharaoh known for her passion for emeralds.
Emerald has been the standard for green colored stones for millennia.
The most desirable emerald colors are bluish green to pure green, with vivid color saturation.
In Emerald expect to see inclusions that dealers like to call an internal "jardin," or garden.
Due to the crystal shape emeralds are commonly cut as rectangular step cuts called emerald cuts.
Because its density is lower, a one-carat emerald will appear larger in size than a one-carat diamond.