mineral

Green Tourmaline (Verdelite)

Elbaite (Na(Li,Al)3Al6(BO3)3Si6O18(OH)4)

AI-generated identification · may be incorrect

Hardness: 7-7.5 (Mohs), Color: emerald green to yellowish-green, Luster: Vitreous, Structure: Trigonal/Hexagonal with vertical striations, Cleavage: Indistinct, SG: 3.06.

Hardness: 7-7

Identified July 7, 2026More mineral →

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Physical properties

Hardness: 7-7.5 (Mohs), Color: emerald green to yellowish-green, Luster: Vitreous, Structure: Trigonal/Hexagonal with vertical striations, Cleavage: Indistinct, SG: 3.06.

Formation & geological history

Formed in granitic pegmatites and metamorphic rocks through hydrothermal processes involving boron-rich fluids during late-stage igneous cooling.

Uses & applications

Highly valued as a gemstone in jewelry, popular for mineral collectors, and used in high-pressure scientific gauges due to piezoelectric properties.

Geological facts

Tourmaline is unique because it is both piezoelectric and pyroelectric, meaning it generates an electrical charge when compressed or heated.

Field identification & locations

Identify by prominent vertical striations on the prism faces and its characteristic triangular cross-section; commonly found in Brazil, Afghanistan, and Namibia.