gems, beryl, emerald, Colombia, gold, shipwrecks, Florida Keys

During the 1970s and 1980s, treasure hunters discovered the centuries-old re-mains of the sunken Spanish galleons Nuestra Senora de Atocha and Santa Mar-garita. Not only did they find massive amounts of silver and gold in coins, bars, and chains, but they also uncovered a number of rough emeralds and several pieces of emerald-set jewelry. Recently, some of the treasures recovered from the Atocha were examined at the Santa Monica office of the GIA Gem Trade Lab-oratory. Gemological testing of the emer-alds revealed inclusions typical of stones mined in Colombia as well as possible ev-idence of extended submersion in s e w -ter. Study of the jewelry revealed a high-karat gold content and fine workmanship that represented methods typical of the era.