Gemstone profile and identification guide
Aegean Opal
Aegean opal is a trade-name opal category and should be handled as opal mineraloid material with seller-specific locality disclosure.
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Overview
Aegean opal is a trade-name opal category and should be handled as opal mineraloid material with seller-specific locality disclosure.
Did you know? Many opal trade names describe color style rather than a formally recognized mineral variety.
Use this profile as a collector reference and educational guide for quick on-page comparison, then validate with the interactive identification system.
Identification
Name: Aegean Opal
Scientific classification: Mineraloid (Opal Trade Name)
Hardness: 5.5 Mohs
Transparency: translucent
Lustre: waxy to vitreous
Crystal system: Amorphous
Primary colour: Blue
Secondary colour: Blue Green
Colour family: Blues
Confirm opal properties (amorphous structure, low RI, SG range) and verify declared source via documentation.
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 treatment/composition disclosures where applicable.
Physical Properties
Hardness category: medium
Hardness value: 5.5 Mohs
Chemical composition: Hydrated silica (SiO2.nH2O)
Crystal system: Amorphous
Common locations: Trade-name material in commerce; source declarations commonly reference opal localities in Europe and other markets
Learn more: Gem-A gemstone education resources.
Colour Variations
Trade-name opal material marketed in pale blue to blue-green tones, commonly without play-of-color.
Optical effects: Opalescence
Detailed Gemology
Mineral species: Opal
Mineral group: Opal mineraloid
Chemical formula: Hydrated silica (SiO2.nH2O)
Mohs hardness: 5.5
Crystal system: Amorphous
Lustre: waxy to vitreous
Transparency: translucent
Streak: White
Cleavage: None
Fracture: Conchoidal to uneven
Specific gravity: 1.98-2.25
Refractive index: 1.37-1.52
Optical phenomena: Opalescence (play-of-color not always present)
Colour range: Blue, blue-green, white
Common inclusions: Potch zones, hydration-related crazing in unstable material
Geological environment: Silica deposition in sedimentary and volcanic settings
Principal mining regions: Trade-name material in commerce; source declarations commonly reference opal localities in Europe and other markets
Important commercial sources: Aegean Opal is a trade descriptor; supplier-specific provenance should be documented for source-critical valuation
Historical significance: Trade names expanded with modern gem marketing channels.
Common treatments: Stabilization and impregnation may occur; disclosure required.
Synthetic or imitation forms: Synthetic opal and glass imitations are common.
Common look-alikes: Blue glass opal imitations, dyed chalcedony, assembled opals
Jewellery uses: Used in cabochons and decorative jewellery emphasizing body color.
Care recommendations: Avoid heat, dehydration, and ultrasonic cleaning; store away from strong temperature changes.
Cross-check profile data with GIA Gem Encyclopedia and Mindat entry for Aegean Opal.
Formation
Opal forms by low-temperature silica gel deposition in voids and fractures.
Origin
Aegean Opal is a trade descriptor; supplier-specific provenance should be documented for source-critical valuation
Uses
Best for: Used in cabochons and decorative jewellery emphasizing body color.
Ideal uses: Protected settings and occasional wear.
Care
Avoid heat, dehydration, and ultrasonic cleaning; store away from strong temperature changes.
Need another candidate? Use advanced gemstone search or return to the identification guide.
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Aegean Opal FAQ
How can I identify Aegean Opal?
Compare hardness (5.5 Mohs), crystal system (Amorphous), colour profile, and lustre (waxy to vitreous) with your sample. Then cross-check related gemstones listed above.
What colour range does Aegean Opal appear in?
Trade-name opal material marketed in pale blue to blue-green tones, commonly without play-of-color.
Where is Aegean Opal commonly used?
Protected settings and occasional wear.. For maintenance, follow the care guidance in this profile.
Scientific References
GIA: general gemstone identity (reviewed) - Batch 05 factual verification pass.
Gem-A: gemological terminology and testing references (reviewed) - Batch 05 factual verification pass.
Mindat: mineral species and principal localities (reviewed) - Batch 05 factual verification pass.
International Gem Society: gem trade context and treatment overview (reviewed) - Batch 05 factual verification pass.