Like waves on a clear blue sea, or twisting wind-swept clouds, these whimsical designs are an artistic expression of spirit and uniqueness. Tanzanite is the new birthstone of December and has a unique purple-blue color. A tanzanite ring is one of the newest fashion trends and is a must for any jewelry collection. The birthstone of December, the intense deep blue color of a london blue topaz ring can evoke thoughts of warm Caribbean nights.