Tourmaline in itself has the most wide range of colors out of all minerals. Though the great majority of it is formed black. It is so varying in color that it was once referred to as the singular name for all crystals. It was said in ancient Egypt that it traveled across the rainbow, gathering all of the colors along the way.
From its mining origins all the way to current day; it has been regarded as a stone of protection in every land that it was unearthed(from Asia to Africa to Europe). For each land of very, very different cultures and religions... to have come to the same intuitive conclusion of its protective qualities- has to say something powerful about this crystal formation.
Scientifically speaking- black tourmaline is incredibly both 'pyroelectric' and 'piezoelectric'. That is actual proof of this crystal being capable of absorbing a large electric charge from multiple types of energy sources, such as friction or temperature changes etc. It holds quite a vibration within its structure. Crystals in general have high vibration and conductivity. However, this crystal absorbs an electric charge from various forms of energy.
That would seem to give merit to the belief that it can absorb and redirect or diffuse negative energies from your body and your environment. It is no wonder that this ranks among the most common and widely used specimens in metaphysics. It is believed to virtually vacuum up all of the negativity in and around you, from bad intentions to electrical interference from electronics, electromagnetic-frequencies, and many other forms of bad energy. Compelling is the fact that like said: it ACTUALLY DOES absorb many forms of electric charges- like a happy little energy sponge. No matter what you believe, physics cannot lie. There is so much more to this awesome crystal than we realize!