0.75"-1.25" Size Black Tourmaline, a member of the Tourmaline family, is a protective stone that repels and blocks negative energies and psychic attacks. Black Tourmaline also aids in the removal of negative energies within a person or a space. Black Tourmaline will cleanse, purify, and transform dense energy into a lighter vibration.. Black Tourmaline, a member of the Tourmaline family, is a protective stone that repels and blocks negative energies and psychic attacks. Black Tourmaline also aids in the removal of negative energies within a person or a space. Black Tourmaline will cleanse, purify, and transform dense energy into a lighter vibration..