Topaz
From imperial orange to electric blue — a versatile and durable gem.
Topaz is an aluminum fluorosilicate mineral available in a wide spectrum of colors. While blue topaz dominates the commercial market (virtually all blue topaz is irradiated and heat-treated from colorless rough), the most valuable variety is Imperial Topaz — a rich orange to pinkish-orange found primarily in Ouro Preto, Brazil. Topaz scores 8 on the Mohs scale, making it quite durable, though it has perfect basal cleavage which means it can split if struck at the right angle. The stone's excellent clarity, large crystal sizes, and affordability make it popular in fashion jewelry.
Physical Properties
| Hardness (Mohs) | 8 |
| Refractive Index | 1.609–1.643 |
| Specific Gravity | 3.49–3.57 |
| Crystal System | Orthorhombic |
| Chemical Formula | Al₂SiO₄(F,OH)₂ |
Color Varieties
Major Sources
Brazil · Nigeria · Sri Lanka · Pakistan · Russia · Mexico
Pricing Factors
Color Variety
Imperial topaz commands the highest prices by far. Natural pink and sherry topaz are also premium. Treated blue topaz is inexpensive — even large stones are affordable.
Treatment
Blue topaz is always irradiated/heated. This is universally accepted and does not impact pricing negatively. Imperial topaz value depends on natural color intensity.
Size
Topaz forms large crystals, so size premiums are modest except for rare Imperial topaz. Blue topaz over 10 carats is common and affordable.
Clarity
Eye-clean clarity is expected. Topaz is a Type I gem — inclusions are rare in gem-quality material.
Care Instructions
Do
- Clean with warm soapy water and a soft brush
- Store in a soft pouch to prevent scratching
- Handle with reasonable care around hard surfaces
Don't
- Don't use ultrasonic cleaners — perfect cleavage means topaz can split under vibration
- Avoid steam cleaning
- Don't expose to sudden temperature changes
Cleaning Method
Warm soapy water and a soft brush. Avoid ultrasonic and steam due to topaz's perfect basal cleavage.
Insider Buying Tips
Blue topaz is a budget-friendly gem — don't overpay for Swiss or London Blue, as large stones are abundant.
Imperial topaz is the only variety with serious collector value — focus your budget here if investing.
Be aware that 'mystic topaz' is a thin coating on colorless topaz that wears off — avoid it for fine jewelry.
Topaz has perfect cleavage — choose protective settings for rings and avoid hard impacts.
Natural pink topaz is extremely rare — most pink topaz on the market is heat-treated from brownish material.
Did You Know?
The 'El-Dorado' topaz from Brazil weighs 31,000 carats and is the largest faceted gemstone in the world.
Ancient Egyptians believed topaz was colored by the sun god Ra.
November babies have topaz as their birthstone, alongside citrine.