Beryl over , and its dimensions were long and in diameter. The largest cut aquamarine gem is the Dom Pedro aquamarine, now housed in the Smithsonian Institution's National Museum of Natural History. The ancient Romans believed that aquamarine would protect against any dangers while travelling at sea, and that it provided energy and cured laziness. Emerald is green beryl, colored by trace amounts of chromium and sometimes vanadium. Most emeralds are highly included, so their brittleness (resistance to breakage) is classified as generally poor. The modern English word "emerald" comes via Middle English "Emeraude", imported from modern French via Old French
Dom Pedro aquamarine Dom Pedro aquamarine The Dom Pedro aquamarine is the world's largest cut aquamarine gem. It was cut from a crystal originally weighing approximately and measuring more than in length. The stone was mined in Pedra Azul, in the state of Minas Gerais in Brazil around 1980, and named after the Brazilian emperors Pedro I and Pedro II. The blue-green gemstone was cut by Bernd Munsteiner into an obelisk form weighing 10,363 carats. The finished dimensions measure tall by wide. The jewel was donated to the Smithsonian Institution by Jane Mitchell and Jeffery Bland. It is housed in the National Museum