Green variety of beryl, mined in Upper Egypt and India from antiquity and in Colombia both before and after the Spanish Conquest. Nero is said to have watched gladiatorial contests through an emerald. The two best-known emeralds are the Devonshire Emerald (London, Nat. Hist. Mus.) and the Patricia Emerald (New York, Amer. Mus. Nat. Hist.). The most famous historical emeralds are the 453 emeralds (totalling 1521 carats) that were taken from the Incas and used in 1593 to decorate the gold Crown of the Andes; its present location is not known.