Gemstone profile and identification guide
Schorl
Schorl is the black iron-rich tourmaline species widely used in mineral and decorative markets.
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Overview
Schorl is the black iron-rich tourmaline species widely used in mineral and decorative markets.
Did you know? Schorl is the most abundant tourmaline species in nature.
Use this profile as a collector reference and educational guide for quick on-page comparison, then validate with the interactive identification system.
Identification
Name: Schorl
Scientific classification: Silicate (Tourmaline Group: Schorl)
Hardness: 7.25 Mohs
Transparency: opaque
Lustre: vitreous to submetallic
Crystal system: Trigonal
Primary colour: Black
Secondary colour: Not specified
Colour family: Blacks
Prismatic tourmaline habit and species chemistry identify schorl.
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 and treatment-sensitive entries include explicit disclosure notes where applicable.
Physical Properties
Hardness category: hard
Hardness value: 7.25 Mohs
Chemical composition: Sodium iron aluminum borosilicate [NaFe3Al6(BO3)3Si6O18(OH)4]
Crystal system: Trigonal
Common locations: Brazil, Pakistan, Afghanistan, Namibia, United States
Learn more: Gem-A gemstone education resources.
Colour Variations
Black iron-rich tourmaline species, typically opaque.
Optical effects: None specified in the current dataset.
Detailed Gemology
Mineral species: Schorl
Mineral group: Tourmaline group
Chemical formula: Sodium iron aluminum borosilicate [NaFe3Al6(BO3)3Si6O18(OH)4]
Mohs hardness: 7.25
Crystal system: Trigonal
Lustre: vitreous to submetallic
Transparency: opaque
Streak: White to gray
Cleavage: Indistinct
Fracture: Conchoidal to uneven
Specific gravity: 3.0-3.3
Refractive index: 1.61-1.66
Optical phenomena: None typically diagnostic
Colour range: Black
Common inclusions: Growth tubes, fractures, zoned structure
Geological environment: Pegmatitic and metamorphic boron-rich settings
Principal mining regions: Brazil, Pakistan, Afghanistan, Namibia, United States
Important commercial sources: Schorl is common in pegmatitic and metamorphic environments worldwide
Historical significance: Important mineralogical member of tourmaline family.
Common treatments: Generally untreated.
Synthetic or imitation forms: Black glass and dyed stones can imitate.
Common look-alikes: Black spinel, onyx, black obsidian
Jewellery uses: Used in carvings, beads, and mineral specimens.
Care recommendations: Durable but can fracture along stress zones; avoid severe impact.
Cross-check profile data with GIA Gem Encyclopedia and Mindat entry for Schorl.
Formation
Forms in boron-rich pegmatites and metamorphic systems.
Origin
Schorl is common in pegmatitic and metamorphic environments worldwide
Uses
Best for: Used in carvings, beads, and mineral specimens.
Ideal uses: Collector minerals and durable dark jewelry accents.
Care
Durable but can fracture along stress zones; avoid severe impact.
Need another candidate? Use advanced gemstone search or return to the identification guide.
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Schorl FAQ
How can I identify Schorl?
Compare hardness (7.25 Mohs), crystal system (Trigonal), colour profile, and lustre (vitreous to submetallic) with your sample. Then cross-check related gemstones listed above.
What colour range does Schorl appear in?
Black iron-rich tourmaline species, typically opaque.
Where is Schorl commonly used?
Collector minerals and durable dark jewelry accents.. For maintenance, follow the care guidance in this profile.
Scientific References
GIA: general gemstone identity (reviewed) - Batch 08 factual verification pass.
Gem-A: gemological terminology and testing references (reviewed) - Batch 08 factual verification pass.
Mindat: mineral species and principal localities (reviewed) - Batch 08 factual verification pass.
International Gem Society: gem trade context and treatment overview (reviewed) - Batch 08 factual verification pass.