Alexandrite engagement rings? Absolutely! Diamonds may be a girl's best friend, but Alexandrite engagement rings are a unique, original, and a far more affordable choice. The birthstone of June, Alexandrite is an amazing and mysterious stone. A created alexandrite ring is a unique and entertaining attention getter. Sapphire is the birthstone of September, and pink sapphire is a very popular gemstone in jewelry today. The bright and happy color of a pink sapphire ring is both playful and trendy.