Also known as Schorl, Black Tourmaline is a popular black semi-precious October birthstone known for its opaque deep black hue and talismanic properties against negativity. With a 7 to 7.5 ranking on the Mohs scale, it makes durable Black Tourmaline Jewelry that detoxifies your body, sucks bad vibes, and turns them into positive ones, soothing worries and bringing inner peace.