Although zircon comes in a wide range of colors, the most popular of these is the blue zircon. This gemstone is so admired because of the brilliantly blue color, and is even confused at times with a blue diamond. The color ranges from pastel to sky blue, and sometimes can be a bright and vivid blue. Not only is it the birthstone for December, but it is also the traditional gift for the fourth wedding anniversary. A blue zircon is an elegant piece that could easily fit in any jewelry collection.