From Egyptian pharaohs to Inca emperors, emerald has enchanted royalty. Cleopatra was known to have a passion for emerald and used it in her royal adornments. The legendary Crown of the Andes, fashioned in colonial South America, is one example of how the Spanish revered the May birthstone. According to lore, its largest stone—now called the Atahualpa emerald—was taken from the last Inca emperor, Atahualpa, by conquistador Francisco Pizarro. The word “emerald” comes from smaragdos, ancient Greek for a green gem. Roman author Pliny the Elder, who died in the 79 CE eruption of Mt. Vesuvius, wrote in his encyclopedic Natural History that “nothing greens greener.” He also stated that the May birthstone had therapeutic properties that helped gem cutters: “(they) have no better method of restoring their eyes than by looking at the emerald, its soft, green color comforting and removing their weariness and lassitude.” Science now proves this belief: The color green relieves stress and eye strain.