mineral

Watermelon Tourmaline in Quartz Matrix

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

Hardness: 7 to 7.5 on Mohs scale. Color: Green outer layer with pink/red core in a white/translucent quartz host. Luster: Vitreous (glassy). Crystal structure: Trigonal/Hexagonal columns. Cleavage: Indistinct/none.

Hardness: 7 to 7
Luster: Vitreous (glassy)

Identified March 19, 2026More mineral →

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Physical properties

Formation & geological history

Formed in granitic pegmatites through hydrothermal activity. As the magma cools, fluid-rich pockets allow for the crystallization of rare minerals like tourmaline. These formations span various geological ages but are common in Precambrian to Mesozoic pegmatite belts.

Uses & applications

Primarily used in high-end jewelry (when gem quality) and as a highly sought-after specimen for mineral collectors. Industrially, tourmaline is used in pressure gauges due to its piezoelectric properties.

Geological facts

The 'watermelon' name comes from the distinct bi-colored nature where green surrounds a pink center. It is one of the few minerals that can be electrically charged just by heating or rubbing it (pyroelectricity and piezoelectricity).

Field identification & locations

Identify in the field by looking for elongated, striated prismatic crystals within white quartz or mica. Key locations include Brazil, Madagascar, Afghanistan, and the United States (Maine and California). Collectors look for sharp color zoning and clarity.

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