Gemstone profile and identification guide
Locality plays an important role in how Tourmaline is understood in the gem trade. That combination of green body colour, 7 Mohs hardness, and vitreous lustre is what usually makes it recognisable in practice. The secondary pink note often matters more than people expect when separating it from lookalikes.
Locality plays an important role in how Tourmaline is understood in the gem trade. That combination of green body colour, 7 Mohs hardness, and vitreous lustre is what usually makes it recognisable in practice. The secondary pink note often matters more than people expect when separating it from lookalikes.
Did you know? Tourmaline is commonly associated with material from Brazil, though the broader trade may draw on multiple localities.
Use this profile as a collector reference and educational guide for quick on-page comparison, then validate with the interactive identification system.
Name: Tourmaline
Scientific classification: Cyclosilicate (Tourmaline Group)
Hardness: 7.25 Mohs
Transparency: transparent
Lustre: vitreous
Crystal system: Trigonal
Primary colour: Green
Secondary colour: Pink
Colour family: Greens
A practical identification pass begins with the visible basics: transparent transparency, vitreous lustre, 7 Mohs hardness, and a hexagonal crystal system. The interaction between green and pink tones is more useful than the primary colour alone when comparing candidates. Useful side-by-side comparisons include Pink Tourmaline, Green Tourmaline, Black Tourmaline.
Status: verified-core-fields
Reference priority: GIA, Gem-A, Mindat, International Gem Society
Core identity fields reviewed against consensus gemological references (GIA/Gem-A/Mindat/IGS).
Some market- and locality-level details may still require citation-grade source notes for publication workflows.
Hardness category: medium
Hardness value: 7.25 Mohs
Chemical composition: Complex borosilicate group (variable species chemistry)
Crystal system: Trigonal
Common locations: Brazil, Afghanistan, Nigeria, Mozambique, Madagascar
Learn more: Gem-A gemstone education resources.
Tourmaline sits in the greens grouping here, usually reading first as green with pink appearing as a secondary note or modifier.
Optical effects: Pleochroism
Mineral species: Tourmaline group
Mineral group: Tourmaline group
Chemical formula: Complex borosilicate group (variable species chemistry)
Mohs hardness: 7.25
Crystal system: Trigonal
Lustre: vitreous
Transparency: transparent
Streak: White
Cleavage: Indistinct
Fracture: Conchoidal to uneven
Specific gravity: 3.00-3.20
Refractive index: 1.61-1.65
Optical phenomena: Pleochroism
Colour range: Green, Pink
Common inclusions: Growth tubes, liquid inclusions, and color-zoning features
Geological environment: Tourmaline occurs in Boron-rich granitic pegmatites and associated hydrothermal systems. Its Trigonal structure reflects the pressure-temperature conditions of those host rocks, with notable occurrences in Brazil, Afghanistan, Nigeria, Mozambique, Madagascar.
Principal mining regions: Brazil, Afghanistan, Nigeria, Mozambique, Madagascar
Important commercial sources: Commercial gem tourmaline is supplied mainly by Brazil and East Africa, with Afghanistan important for some varieties
Historical significance: Tourmaline has become a cornerstone of modern colored-gem trade due to wide color diversity.
Common treatments: Heat treatment is used for some colors; other treatments vary by variety and source lot.
Synthetic or imitation forms: Glass and assembled imitations exist; synthetic true tourmaline is not common in jewelry trade.
Common look-alikes: pink tourmaline, green tourmaline, black tourmaline
Jewellery uses: Tourmaline is used chiefly for A good fit for collectors and jewellers looking for visible character without needing the highest hardness category.. In the trade it is commonly fashioned as faceted stones, calibrated cuts, and higher-clarity collector pieces, with Mohs hardness 7.25 guiding suitable jewellery applications.
Care recommendations: Tourmaline should be cleaned with lukewarm water, mild soap, and a soft brush. At Mohs 7.25 in the Trigonal system, avoid steam cleaners, harsh chemicals, and high-impact wear. Store separately from harder gems to minimise abrasion and edge wear.
Cross-check profile data with GIA Gem Encyclopedia and Mindat entry for Tourmaline.
Tourmaline is a Tourmaline group material with chemistry Complex borosilicate group (variable species chemistry). It develops in Boron-rich granitic pegmatites and associated hydrothermal systems, and economically significant production is associated with Brazil, Afghanistan, Nigeria, Mozambique, Madagascar.
Commercial gem tourmaline is supplied mainly by Brazil and East Africa, with Afghanistan important for some varieties
Best for: Tourmaline is used chiefly for A good fit for collectors and jewellers looking for visible character without needing the highest hardness category.. In the trade it is commonly fashioned as faceted stones, calibrated cuts, and higher-clarity collector pieces, with Mohs hardness 7.25 guiding suitable jewellery applications.
Ideal uses: A good fit for collectors and jewellers looking for visible character without needing the highest hardness category.
Tourmaline should be cleaned with lukewarm water, mild soap, and a soft brush. At Mohs 7.25 in the Trigonal system, avoid steam cleaners, harsh chemicals, and high-impact wear. Store separately from harder gems to minimise abrasion and edge wear.
Need another candidate? Use advanced gemstone search or return to the identification guide.
Compare hardness (7.25 Mohs), crystal system (Trigonal), colour profile, and lustre (vitreous) with your sample. Then cross-check related gemstones listed above.
Tourmaline sits in the greens grouping here, usually reading first as green with pink appearing as a secondary note or modifier.
A good fit for collectors and jewellers looking for visible character without needing the highest hardness category.. For maintenance, follow the care guidance in this profile.
GIA: general gemstone identity (reviewed) - Reviewed as a direct core gemstone profile.
Gem-A: gemological education and terminology (reviewed) - Reviewed as a direct core gemstone profile.
Mindat: mineral species and locality index (reviewed) - Reviewed as a direct core gemstone profile.
International Gem Society: collector-facing gem reference (reviewed) - Reviewed as a direct core gemstone profile.
