Gemstone profile and identification guide
Liddicoatite
Liddicoatite is a calcium-rich tourmaline species known for striking multicolor zoning patterns.
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Overview
Liddicoatite is a calcium-rich tourmaline species known for striking multicolor zoning patterns.
Did you know? Liddicoatite can display concentric color zoning unlike many other gem tourmalines.
Use this profile as a collector reference and educational guide for quick on-page comparison, then validate with the interactive identification system.
Identification
Name: Liddicoatite
Scientific classification: Silicate (Tourmaline Group: Liddicoatite)
Hardness: 7.5 Mohs
Transparency: transparent
Lustre: vitreous
Crystal system: Trigonal
Primary colour: Multicolor
Secondary colour: Pink
Colour family: Multi
Advanced analytical testing may be required to separate liddicoatite from elbaite in some stones.
Verification Status
Status: verified-core-fields
Reference priority: GIA, Gem-A, Mindat, International Gem Society
Core identity, locality, and physical-property fields reviewed against standard gemological references.
Trade-name entries include conservative composition/treatment disclosures where needed.
Physical Properties
Hardness category: hard
Hardness value: 7.5 Mohs
Chemical composition: Calcium-rich complex tourmaline species (compositionally variable)
Crystal system: Trigonal
Common locations: Madagascar, Sri Lanka
Learn more: Gem-A gemstone education resources.
Colour Variations
Complexly zoned multicolor tourmaline species, often with concentric or sector zoning.
Optical effects: Pleochroism, Color Zoning
Detailed Gemology
Mineral species: Liddicoatite
Mineral group: Tourmaline group
Chemical formula: Calcium-rich complex tourmaline species (compositionally variable)
Mohs hardness: 7.5
Crystal system: Trigonal
Lustre: vitreous
Transparency: transparent
Streak: White
Cleavage: Indistinct
Fracture: Conchoidal to uneven
Specific gravity: 3.0-3.3
Refractive index: 1.61-1.65
Optical phenomena: Pleochroism and complex zoning
Colour range: Pink, green, brown, multicolor combinations
Common inclusions: Growth tubes, zoning boundaries, fractures
Geological environment: Complex lithium-bearing pegmatites
Principal mining regions: Madagascar, Sri Lanka
Important commercial sources: Gem liddicoatite is classically linked to Madagascar and Sri Lankan occurrences
Historical significance: Important collector species in advanced tourmaline mineralogy.
Common treatments: Heat treatment possible in some stones.
Synthetic or imitation forms: Colored glass and synthetic alternatives can imitate appearance.
Common look-alikes: Elbaite tourmaline, multicolor quartz imitations
Jewellery uses: Liddicoatite is used chiefly for Collector-grade stones showcasing exceptional zoning.. In the trade it is commonly fashioned as faceted stones, calibrated cuts, and higher-clarity collector pieces, with Mohs hardness 7.5 guiding suitable jewellery applications.
Care recommendations: Durable but included zones can be brittle; avoid impact on thin faceted edges.
Cross-check profile data with GIA Gem Encyclopedia and Mindat entry for Liddicoatite.
Formation
Forms in complex pegmatitic systems with evolving chemistry during crystal growth.
Origin
Gem liddicoatite is classically linked to Madagascar and Sri Lankan occurrences
Uses
Best for: Liddicoatite is used chiefly for Collector-grade stones showcasing exceptional zoning.. In the trade it is commonly fashioned as faceted stones, calibrated cuts, and higher-clarity collector pieces, with Mohs hardness 7.5 guiding suitable jewellery applications.
Ideal uses: Collector-grade stones showcasing exceptional zoning.
Care
Durable but included zones can be brittle; avoid impact on thin faceted edges.
Need another candidate? Use advanced gemstone search or return to the identification guide.
Related gemstones by colour
Related gemstones by hardness
Commonly confused gemstones
Liddicoatite FAQ
How can I identify Liddicoatite?
Compare hardness (7.5 Mohs), crystal system (Trigonal), colour profile, and lustre (vitreous) with your sample. Then cross-check related gemstones listed above.
What colour range does Liddicoatite appear in?
Complexly zoned multicolor tourmaline species, often with concentric or sector zoning.
Where is Liddicoatite commonly used?
Collector-grade stones showcasing exceptional zoning.. For maintenance, follow the care guidance in this profile.
Scientific References
GIA: general gemstone identity (reviewed) - Batch 06 factual verification pass.
Gem-A: gemological terminology and testing references (reviewed) - Batch 06 factual verification pass.
Mindat: mineral species and principal localities (reviewed) - Batch 06 factual verification pass.
International Gem Society: gem trade context and treatment overview (reviewed) - Batch 06 factual verification pass.