Black Tourmaline is one of the strongest protection stones. It transmutes negativity and electro-magnetic smog.
On the physical level Black Tourmaline is soothing when feeling low and energy deprived. It activates the body's meridians and metabolism.
On the psychological levelBlack Tourmaline acts like an invisible shield. It helps to put an energetic boundary between yourself and others, so that you don’t pick up other people’s energy, which happens a lot if you are sensitive. It also is a must-have if you are a frequent flyer.