May's birthstone is the emerald.  The stone was once believed to prevent epilepsy, stop bleeding, cure dysentery and fever, and protect the wearer from panic.  The emerald was once linked to health and the curing of ailments, as well as being associated with the ability to see in to the future, giving them an almost bewitching, magical reputation. Emeralds are known to be lucky in love, offer good fortune, and bring tranquility to the soul. Emeralds also represent fertility and rebirth.