Black and gold make a beautiful and elegant combination. A black onyx ring is a perfect accessory for any outfit. The birthstone of May, an emerald ring symbolizes the eternally returning spring. The velvety green color of emerald is a perfect match for spring and summer fashions. 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.