The prism faces are striated lengthwise. In cross section, all tourmalines will appear predominantly triangular in shape with some crystals showing a hexagon. Doubly terminated crystals are hemimorphic meaning that the two ends of the crystal are not exactly alike. Massive forms can also be found. Cleavage is absent although there is basal parting.
Fracture is uneven to conchoidal.
Luster is vitreous. Associated Minerals include those associated with metamorphic rocks such as micas , feldspars and quartz . Notable Occurances include brazil and some other South American countries, and Africa. Best Field Indicators are crystal habit, triangular cross-section, color and hardness.