The most expensive blue diamond ever sold was the Cullinan Blue Diamond, which sold for $57.5 million in 2014.
Pink diamonds are also very rare and valuable. They are formed when trace amounts of manganese are trapped in the diamond's crystal structure.
Red diamonds are the rarest of all diamonds. They are formed when microscopic platelets of iron are trapped in the diamond's crystal structure. Red diamonds can range in color from a light red to a deep, vivid red.
Emeralds are a type of beryl that is colored green by trace amounts of chromium. Emeralds are found in a variety of shades of green, from a light green to a deep, vivid green.
Jadeite is a type of jade that is colored green by trace amounts of chromium. Jadeite is found in a variety of shades of green, from a light green to a deep, vivid green.