Mineralpedia Details for Tourmaline
Refers to the Tourmaline Group, and is not one single mineral. Common members of the group include Elbalite, Schorl, and Dravite, while lesser known members include Uvite, Liddicoatite, and Buergerite. Most if not all tourmalines are pyroelectric and piezoelectric and will generate a charge in response to temperature and pressure changes, respectively. Tourmalines are highly variable in color and appear generally as prismatic, elongated crystals that are heavily striated.
Tourmaline from Himalaya mine, San Diego Co., California, United States
Tourmaline from Gamatha, Kunar Province, Afghanistan
Tourmaline from Paprook, Kunar prov., Afghanistan
Tourmaline from Shengus, Gilgit-Skardu road, Northern Areas, Pakistan
Deep green zoned Indicolite Tourmaline with a blue, terminated cap. Overall 4.5 x 2 x 2cm.
Tourmaline from Mong Hsu, Shan State, Burma
A complete hemihedral chrome tourmaline terminated on both end. As you can see both sides, however, have detachment points from matrix. The color is a gorgeous deep gemmy emerald green.