Pure vibrant red to slightly purplish red; colored by trace chromium substituting for aluminum in the crystal lattice....
Chemical formula
Al₂O₃ + Cr³⁺ (Aluminum Oxide with trace Chromium)
Corundum • Corundum
Yellow Sapphire
Pale lemon yellow to rich canary and golden amber hues.
Al₂O₃ + Fe³⁺ (Aluminum Oxide with trace Ferric Iron and color centers)Mohs 9.0 Mohs
Mineralogical & Gemological Profile
| Mineral Family | Corundum |
|---|---|
| Mineral Species | Corundum |
| Gemological Variety | Yellow Sapphire |
| Chemical Composition | Al₂O₃ + Fe³⁺ (Aluminum Oxide with trace Ferric Iron and color centers) |
| Crystal System | Trigonal |
| Mohs Hardness | 9.0 Mohs |
| Specific Gravity | 3.95 – 4.03 |
| Refractive Index | 1.762 – 1.770 |
Color Characteristics & Optical Behavior
Pale lemon yellow to rich canary and golden amber hues.
Geological Context & Pakistani / Global Localities
Recovered primarily from alluvial deposits in Sri Lanka (Ratnapura), Madagascar, Tanzania, and Australia.
Collector Interest & Rarity Factors
Natural iron-colored canary yellow sapphires with high clarity and crisp step or brilliant faceting are prized by connoisseurs.
Fine Jewelry Applications
Popular in both contemporary solitaire rings and traditional South Asian gold settings.
Treatment Considerations & Disclosure
May be natural, heat-treated, beryllium-diffused (producing intense orange-yellow), or irradiated (which can fade in sunlight). Full treatment disclosure is essential.
Care & Cleaning Instructions
Clean with warm soapy water. If a stone has color-center irradiation treatment, avoid prolonged exposure to intense heat or direct UV lamps.
Traditional Meaning
Traditional Symbolism & Cultural Heritage
Known as 'Pukhraj' in South Asian tradition, historically associated with prosperity, scholarship, and auspicious beginnings.
Note: Cultural and birthstone traditions are presented strictly as historical folklore, never as scientifically verified medical or metaphysical effects.
Corundum
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