The garnet gemstone is sometimes referred to as a 'stone of health'. It is supposed to aid in the circulation of energy. It is said to remove nightmares and depression and help heal various skin conditions. It is affiliated with the root chakra and is said to help stimulate the pituitary gland.
And what about the February birthstone; the amethyst? According to the writers at Wikipedia amethyst is no less than 'a symbol of heavenly understanding, and of the pioneer in thought and action on the philosophical, religious, spiritual and material planes'.
Wikipedia has much more to say about the amethyst birthstone:
Tradition maintains that amethyst assists those who wear it in maintaining their faithfulness, causing peace and calmness of mind. It was often carried by soldiers on the shafts of spears and on swords as a charm against death, being thought to bring calmness and victory in battle. However it is also thought that the protection and long life that amethyst owner has is being drawn from people nearby/enemies killed, thus stealing other's lifeforce in return of prolonging theirs. It is useful for the revelation of prophetic truth. It is said to strengthen wisdom, faith and religion, and is an aid in prayer and in dreaming. It is also said to be a charm against witchcraft, poison (it warns of the presence of poison by dimming), and evil thoughts; it is an aid to chastity, a power against all forms of overindulgence, and a strengthener of the mind. It is used as a charm for securing the favor of people of wealth, influence and power, people with prophetic ability, poets, travelers, publishers, and others. Ranking members of the Catholic Church traditionally wear rings set with a large amethyst as part of their office.
Bound to the left wrist, the amethyst is said to enable the wearer to see the future in dreams. It represses evil thoughts and actions, gives a keen business sense, and warns of ill health. The amethyst attracts love and good luck, and helps to prevent drunkenness.
Geez, with credentials like this, I better run out and get myself an amethyst ;-)