Emerald is a rich green gemstone that is a variety of the mineral beryl. It owes its color to minute amounts of chromium in the crystals. Pure beryl is beryllium aluminum silicate. The value of an emerald lies in its color and its freedom from flaws and inclusions (other substances enclosed in the crystals). An emerald with a blue tint is more valuable than one with a yellow tint. Most emerald crystals contain minute fractures, which are sometimes called veils, and various kinds of inclusions. Perfect emeralds are very rare and therefore may be more expensive than diamonds. Emeralds are harder than quartz, but not as hard as sapphire.
The finest emeralds are obtained from Colombia. Afghanistan, Brazil, India, Madagascar, Pakistan, Russia, Zambia, and Zimbabwe also produce emeralds. In the United States, North Carolina has produced some emeralds. Emeralds may be produced synthetically. Emerald is the birthstone for May.
