Comparison · Precious Stones vs Semi-Precious Stones
Sapphire vs Tanzanite
Sapphire and Tanzanite are easy to confuse. Sapphire is harder (Mohs 9) than Tanzanite (Mohs 6.5), so Sapphire will scratch Tanzanite and not the other way round. It scratches glass and a steel knife and cannot be scratched by a steel file. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Sapphire and Tanzanite
- Sapphire is harder (Mohs 9) than Tanzanite (Mohs 6.5), so Sapphire will scratch Tanzanite and not the other way round. It scratches glass and a steel knife and cannot be scratched by a steel file.
- Sapphire feels noticeably heavier for its size (specific gravity 4 versus 3.35 for Tanzanite).
- They overlap in blue, but Sapphire also comes in pink, yellow, orange, green, and white and Tanzanite also comes in purple.
- Well-formed crystals give it away: Sapphire is trigonal, Tanzanite is orthorhombic.
Sapphire vs Tanzanite properties
| Property | Sapphire | Tanzanite |
|---|---|---|
| Type | Precious Stones | Semi-Precious Stones |
| Mohs hardness | 9 | 6.5 |
| Luster | adamantine | vitreous |
| Streak | White | White |
| Transparency | transparent | transparent |
| Specific gravity | 4 | 3.35 |
| Crystal system | trigonal | orthorhombic |
| Common colors | Blue, Pink, Yellow, Orange, Green, White | Blue, Violet, Purple |
| Rarity | rare | legendary |
| Typical specimen value | $500–$50000+ | $300–$10000+ |
Which is more valuable?
Sapphire is usually the more valuable of the two: a typical collector specimen runs about $5000 against $1000 for Tanzanite, and premium Sapphire can reach $50000 or more.
About Sapphire
Sapphire is a variety of corundum in any color except red. Blue sapphires are most prized, especially the legendary Kashmir stones.
About Tanzanite
Tanzanite is a blue-violet variety of zoisite found only in Tanzania. It's 1,000 times rarer than diamond and was only discovered in 1967.
Sapphire vs Tanzanite FAQ
Is Sapphire the same as Tanzanite?
No. Sapphire is a precious stone while Tanzanite is a semi-precious stone. Sapphire is harder (Mohs 9) than Tanzanite (Mohs 6.5), so Sapphire will scratch Tanzanite and not the other way round. It scratches glass and a steel knife and cannot be scratched by a steel file.
How can you tell Sapphire from Tanzanite?
Sapphire is harder (Mohs 9) than Tanzanite (Mohs 6.5), so Sapphire will scratch Tanzanite and not the other way round. It scratches glass and a steel knife and cannot be scratched by a steel file. Sapphire feels noticeably heavier for its size (specific gravity 4 versus 3.35 for Tanzanite). They overlap in blue, but Sapphire also comes in pink, yellow, orange, green, and white and Tanzanite also comes in purple.
Which is harder, Sapphire or Tanzanite?
Sapphire is harder: Mohs 9 against Mohs 6.5 for Tanzanite.
Which is more valuable, Sapphire or Tanzanite?
Sapphire is usually the more valuable of the two: a typical collector specimen runs about $5000 against $1000 for Tanzanite, and premium Sapphire can reach $50000 or more.
