Sapphire vs Tanzanite
Sapphire and tanzanite are two of the most popular blue gemstones, and they are frequently compared by shoppers looking for the perfect blue stone. While both offer stunning blue hues, they differ significantly in durability, rarity, price, and suitability for different types of jewelry.
| Factor | Sapphire | Tanzanite |
|---|
| Mineral | Corundum | Zoisite |
| Mohs Hardness | 9 | 6 – 7 |
| Color | Pure blue to slightly violet-blue | Blue-violet with color shift |
| Sources | Sri Lanka, Myanmar, Madagascar, Montana | Tanzania only (single source) |
| Rarity | Rare in fine quality; multiple sources | Extremely rare (one deposit worldwide) |
| Price Range | $200 – $30,000+ per carat | $100 – $1,500 per carat |
| Treatments | Heat treatment (standard) | Heat treatment (virtually universal) |
| Birthstone | September | December (alternative) |
Color Comparison
Both stones display blue, but the character is different. Sapphire shows a pure, rich blue that can range from velvety cornflower (Kashmir-type) to deep royal blue. Tanzanite displays a distinctive blue-violet that shifts between blue and purple depending on the viewing angle and lighting (pleochroism). Tanzanite tends to have more violet in its blue, while fine sapphire is a purer blue. In candlelight or warm lighting, tanzanite shifts noticeably toward purple.
Durability — The Key Difference
This is the most important practical distinction. Sapphire at 9 on the Mohs scale is exceptionally durable—one of the best gemstones for rings worn every day. Tanzanite at 6–7 is significantly softer and more fragile. Tanzanite can chip or scratch with daily wear, making it better suited for earrings and pendants than for everyday rings. If you do choose tanzanite for a ring, select a protective bezel setting.
Rarity & Value
Tanzanite is geologically rarer than sapphire—it comes from a single deposit in Tanzania that is estimated to be depleted within 20–30 years. However, sapphire commands higher prices per carat because of its superior durability, historical prestige, and proven long-term value. Fine sapphires have consistently appreciated over decades. Tanzanite offers exceptional color and rarity at a lower price point, potentially making it a collectible gem as the supply diminishes.
Which Should You Choose?
Choose sapphire if: You want a durable blue gemstone for an engagement ring or daily-wear jewelry. Sapphire is the safer choice for any piece that will be worn frequently.
Choose tanzanite if: You love the unique blue-violet color shift, want a rarer gemstone at a lower price point, or are buying earrings, pendants, or special-occasion rings. Tanzanite offers extraordinary beauty for its price.
Browse our sapphire jewelry and tanzanite jewelry collections.