mineral

Tourmaline (Multi-colored)

Complex Borosilicate (Na,Ca)(Li,Mg,Al,Fe)3Al6(BO3)3Si6O18(OH)4

Hardness: 7-7.5 (Mohs scale); Color: Pink, green, black, and blue (often in the same strand); Luster: Vitreous to sub-vitreous; Crystal structure: Trigonal; Cleavage: Indistinct; Specific gravity: 3.0-3.3

Hardness: 7-7
Color: Pink, green, black, and blue (often in the same strand)
Luster: Vitreous to sub-vitreous

Identified March 18, 2026More mineral →

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Physical properties

Formation & geological history

Formed in igneous pegmatites or metamorphic rocks like schist and marble. Their formation involves late-stage hydrothermal activity rich in boron and alkali elements.

Uses & applications

Predominantly used as a gemstone in necklaces and bracelets, and in minor industrial applications for its piezoelectric and pyroelectric properties.

Geological facts

Known as the 'Rainbow Gemstone' because it can be found in almost any color. Ancient legend says it traveled along a rainbow and gathered all the colors.

Field identification & locations

Identify by its hardness and unique pleochroism. Found globally in Brazil, Madagascar, Africa, and Afghanistan. Collectors should look for bead transparency and vibrant color saturation.

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