The usual size for this is 1 inch by 1.5 inches. We recommend to buy it with 24 inches chain. The tourmaline used for this has no hole. the aluminum wire holds the whole stone.
It is one of the most powerful crystals for protection and elimination of negative energy. It helps to put an energetic boundary between you and others, so that you don’t pick up unwanted energies. Wear this crystal for protection against whiners, or emotional vampires who burden you with their problems but do nothing to improve their situations