Amethyst engagement rings? Absolutely! Diamonds may be a girl's best friend, but Amethyst engagement rings are a unique, original, and a far more affordable choice. As the gem of peace and tranquility, amethyst is mesmerizingly beautiful. A durable and affordable gem, an amethyst ring is excellent for every day wear. Black and gold make a beautiful and elegant combination. A black onyx ring is a perfect accessory for any outfit. 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.