Pink tourmaline is a birthstone of October, along with opal, and is a truly special gem. The deep rosy color of a pink tourmaline ring will be sure to attract attention. 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. 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.