Fire Opal engagement rings? Absolutely! Diamonds may be a girl's best friend, but Fire Opal engagement rings are a unique, original, and a far more affordable choice. This birthstone of October embodies the orange and red colors of a warming fire. The fiery sparkle of this gem makes a fire opal ring become the center of conversation 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.