7.0 on the Mohs scale.

Often found in pegmatites, black tourmaline is rich in iron, and very common. Tourmaline and opal are the birthstones of the month of October. Tourmaline is the national gemstone of the United States.

Opaque and completely black. Black spinel and black tourmaline are both excellent choices for making jewelry with black gemstones.

Black tourmaline is not enhanced.

More information on gemstone enhancements.

Schorl is a member of the Tourmaline gemstone family.