The Blue Heart Diamond Ring. This carat heart-shaped, brilliant cut blue diamond was faceted by French jeweler Atanik Eknayan of Paris in from a carat piece of rough. The stone was purchased by the French jeweler, Pierre Cartier in
Crater Lake is a caldera lake in the Crater Lake National Park (Oregon, USA). It's known for water clarity and a deep blue color. Crater Lake partly fills a deep caldera which was formed ages ago by the collapse of the Mount Mazama volcano.