Friendship, love and loyalty are represented by this historic celtic design. A London Topaz claddagh ring with your birthstone or favorite color makes it even more significant. The birthstone of December, the intense deep blue color of a london blue topaz ring can evoke thoughts of warm Caribbean nights. One of the oldest gemstones in history, garnet is the birthstone of January. Garnet rings have been popular since Victorian times, and are treasured for their deep red color.