Out of all the Tourmaline varieties, black Tourmaline or Schorl is by far the most common and abundant. It is estimated that out of all the Tourmaline on earth, 95% of it is black Tourmaline. It is highly regarded by collectors of minerals because of the often perfect crystal shape found in nature. They crystals can be very lustrous (shinny) and are considered to be one of the most beautiful black crystals available.
Since Schorl is part of Tourmaline family it shares the same properties. It is a very durable and tough gemstone. Black Tourmaline has a MOHS hardness of 7.5 so it is perfect for use as jewellery. However most of the time it is used as a specimen so this same hardness will help preserve the specimen for years.