Black Tourmaline crystal is a powerful stone for protection against negative energy of all kinds, as well as being a strong spiritual grounding stone.
This is one of the most popular crystals to be used for metaphysical purposes. Many people, and I believe this is the best protection stone that you can use.
Also known as Schorl, it encourages positive attitudes, good luck and happiness, regardless of the circumstances that you find yourself in.
They are wonderful aids to both the professional healer and the average person who wants a stone that will be a positive force for good in your life, as it creates a positive attitude and mindset.