Like waves on a clear blue sea, or twisting wind-swept clouds, these whimsical designs are an artistic expression of spirit and uniqueness. Sapphire is the birthstone of September, and pink sapphire is a very popular gemstone in jewelry today. The bright and happy color of a pink sapphire ring is both playful and trendy. The birthstone of December, the intense deep blue color of a london blue topaz ring can evoke thoughts of warm Caribbean nights.