mineral

Tourmaline crystals

Elbaite tourmaline; complex boron silicate, commonly approximated as Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

AI-generated identification · may be incorrect

Hardness 7–7.5 Mohs; typically green, blue-green, yellow-green, or black, with vitreous luster, prismatic striated crystals, and no prominent cleavage. The visible pieces are likely rough, terminated or broken crystal fragments, possibly mixed elbaite and schorl.

Identified September 22, 2026More mineral →

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At a glance

Common name: Tourmaline crystals
Scientific name: Elbaite tourmaline; complex boron silicate, commonly approximated as Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄
Category: mineral
Identified: September 22, 2026
Method: Standard

AI Estimated Value

Approximately $10–$100 for common rough mixed pieces; $100–$1,000+ for large, sharply terminated or vividly colored crystals, with fine gem material potentially much higher.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Forms mainly in lithium-rich granitic pegmatites as magma cools and volatile fluids concentrate rare elements; crystals are generally geologically young relative to host rocks, commonly hundreds of millions of years old. Important sources include Brazil, Afghanistan, Pakistan, Madagascar, Namibia, Mozambique, and the United States.

Uses & applications

Gem-quality transparent material is cut into jewelry; opaque or fractured crystals are sold as specimens and used decoratively. Tourmaline’s piezoelectric and pyroelectric behavior has niche technical applications.

Geological facts

Longitudinal striations and strongly variable color zoning are characteristic. Green tourmaline is commonly called verdelite; black schorl is the most abundant tourmaline species.

Field identification & locations

Identify by prismatic, lengthwise-striated crystals, triangular or rounded-triangular cross-sections, strong color zoning, and hardness above glass. Confirm species with chemistry or spectroscopy; similar beryl, epidote, and glass are possibilities.