Tanzanite is one of the rarest gemstones on Earth, found in only one location: the Merelani Hills of northern Tanzania. Discovered in 1967, this mesmerizing blue-violet gemstone was named by Tiffany & Co. after its country of origin and has become one of the most popular colored stones in modern jewelry.
The Rarity Factor
Tanzanite is estimated to be 1,000 times rarer than diamond. Its single source deposit is expected to be exhausted within 20-30 years at current mining rates. This scarcity, combined with growing consumer demand, makes tanzanite a compelling choice for both jewelry and potential appreciation.
Color: The Blue-Violet Spectrum
Tanzanite exhibits trichroism — it shows different colors when viewed from different angles: blue, violet, and burgundy. The most valuable tanzanites show a vivid blue-violet face-up color with strong saturation. Color is caused by vanadium (V3+) in the zoisite crystal structure.
| Color Grade | Description | Price Multiplier |
|---|---|---|
| Vivid Blue-Violet | Intense blue with violet flash, strong saturation | 2.5-4x |
| Strong Blue-Violet | Good blue-violet, decent saturation | 1.5-2.5x |
| Medium Blue-Violet | Noticeable color, lighter saturation | 0.8-1.5x |
| Light Blue-Violet | Pale, delicate color | 0.3-0.8x |
| Grayish/Brownish | Poor color, modifiers dominate | 0.2-0.5x |
Heat Treatment: Standard and Expected
Virtually all tanzanite (95%+) is heat-treated at 350-450°C to convert the natural brownish/reddish color to the desirable blue-violet. The treatment is permanent, stable, and universally accepted. Untreated tanzanite is rare and usually shows a brownish or greenish color that most consumers find less attractive.
Clarity and Quality
Tanzanite is typically eye-clean (VS clarity or better) in commercial sizes. Inclusions are more common in larger stones (5ct+). The most common inclusions are fingerprints, needle-like growth tubes, and graphite crystals. Eye-clean tanzanite is the standard for fine jewelry.
Pricing by Size
| Size | Wholesale Price (per ct) | Notes |
|---|---|---|
| 3-5mm (0.2-0.6ct) | $15-60 | Commercial jewelry |
| 6-8mm (0.8-2ct) | $50-200 | Rings, pendants |
| 9-12mm (2-5ct) | $150-500 | Statement pieces |
| 13-16mm (5-10ct) | $400-1,200 | High-end, rare |
| 17mm+ (10ct+) | $1,000-3,000+ | Collector/investment |
Tanzanite pricing has a significant "size jump" above 5 carats because large, clean, well-colored rough is extremely rare. Fine tanzanite over 10 carats can rival sapphire pricing.
Durability and Care
Tanzanite rates 6.5-7 on the Mohs scale, making it softer than sapphire or ruby. It has moderate toughness and should be protected from hard knocks. Tanzanite is suitable for pendants, earrings, and occasional-wear rings. For daily wear, protective settings are recommended.
Clean with warm soapy water and a soft brush. Avoid ultrasonic cleaners, steam cleaners, and harsh chemicals, as these can damage the stone or affect the heat treatment.
Why Retailers Love Tanzanite
- Unique color — Blue-violet is distinctive and complements both white and yellow metals
- High margins — Lower wholesale cost than sapphire with strong perceived value
- Scarcity story — Single-source rarity is a powerful selling point
- Large sizes available — Eye-clean stones over 5ct are obtainable at reasonable prices
- December birthstone — Steady birthday demand
- Trending — Growing popularity driven by celebrity and royal appearances
Frequently Asked Questions
Why is tanzanite so rare?
Tanzanite is found in only one location — the Mererani Hills of Tanzania — in a geological deposit just 4km wide. At current mining rates, the deposit is expected to be exhausted within 20-30 years, making it significantly rarer than diamond.
Is all tanzanite heat-treated?
Virtually all (95%+) commercial tanzanite is heat-treated to convert natural brownish color to blue-violet. The treatment is permanent, stable, and universally accepted. There is no premium for untreated material because the natural color is less desirable.
Can tanzanite be worn every day?
Tanzanite is 6.5-7 Mohs with moderate toughness. It is suitable for pendants and earrings with no concerns. For rings, protective bezel settings and occasional (rather than daily) wear are recommended.
What color tanzanite is best?
The most valuable tanzanite shows a vivid blue-violet face-up with strong saturation and a violet flash when tilted. Deeper blue is generally preferred over lighter material, though very dark stones can appear blackish in low light.
For more expert gemstone and jewelry guidance, explore our knowledge base or contact our sourcing team at service@holycome.com for wholesale inquiries.