The Medici Emerald — Martin Woodhouse

In 1478 Lorenzo de Medici, ruler of Florence, ended his wars and with the other Italian city-states. But beneath the peaceful surface, deadly rivalry still raged between Florence and Venice. At stake was a treasure that Venice was determined to obtain: a fabulous emerald, on which was inscribed a vital military secret that would tip the balance of power int he Mediterranean. And this emerald was in the hand of the young man who was at once an artist and a dreamer, and one of the Medicis' most trusted agents: Leonardo da Vinci.