Comparison · Semi-Precious Stones vs Minerals
Lapis Lazuli vs Pyrite
Lapis Lazuli and Pyrite are easy to confuse. Pyrite is harder (Mohs 6.5) than Lapis Lazuli (Mohs 5.5), so Pyrite will scratch Lapis Lazuli and not the other way round. It is about as hard as window glass: a knife barely marks it, while a steel file (Mohs 6.5) will. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Lapis Lazuli and Pyrite
- Pyrite is harder (Mohs 6.5) than Lapis Lazuli (Mohs 5.5), so Pyrite will scratch Lapis Lazuli and not the other way round. It is about as hard as window glass: a knife barely marks it, while a steel file (Mohs 6.5) will.
- Streak color differs: Lapis Lazuli leaves a light blue streak on unglazed porcelain, Pyrite leaves greenish-black.
- Luster is different: Lapis Lazuli is vitreous while Pyrite is metallic.
- Pyrite feels noticeably heavier for its size (specific gravity 5 versus 2.8 for Lapis Lazuli).
- They overlap in yellow, but Lapis Lazuli also comes in blue.
Lapis Lazuli vs Pyrite properties
| Property | Lapis Lazuli | Pyrite |
|---|---|---|
| Type | Semi-Precious Stones | Minerals |
| Mohs hardness | 5.5 | 6.5 |
| Luster | vitreous | metallic |
| Streak | Light blue | Greenish-black |
| Transparency | opaque | opaque |
| Specific gravity | 2.8 | 5 |
| Crystal system | cubic | cubic |
| Common colors | Deep Blue, Blue, Blue with gold flecks | Brass Yellow, Pale Gold |
| Rarity | uncommon | common |
| Typical specimen value | $10–$500+ | $2–$100+ |
Which is more valuable?
Lapis Lazuli is usually the more valuable of the two: a typical collector specimen runs about $50 against $15 for Pyrite, and premium Lapis Lazuli can reach $500 or more.
About Lapis Lazuli
Lapis lazuli is a deep blue metamorphic rock prized since antiquity. The golden flecks are pyrite inclusions, while the blue comes from lazurite.
About Pyrite
Pyrite, commonly known as 'fool's gold,' is an iron sulfide with a metallic luster and pale brass-yellow color. Despite its name, it has significant industrial uses.
Lapis Lazuli vs Pyrite FAQ
Is Lapis Lazuli the same as Pyrite?
No. Lapis Lazuli is a semi-precious stone while Pyrite is a mineral. Pyrite is harder (Mohs 6.5) than Lapis Lazuli (Mohs 5.5), so Pyrite will scratch Lapis Lazuli and not the other way round. It is about as hard as window glass: a knife barely marks it, while a steel file (Mohs 6.5) will.
How can you tell Lapis Lazuli from Pyrite?
Pyrite is harder (Mohs 6.5) than Lapis Lazuli (Mohs 5.5), so Pyrite will scratch Lapis Lazuli and not the other way round. It is about as hard as window glass: a knife barely marks it, while a steel file (Mohs 6.5) will. Streak color differs: Lapis Lazuli leaves a light blue streak on unglazed porcelain, Pyrite leaves greenish-black. Luster is different: Lapis Lazuli is vitreous while Pyrite is metallic.
Which is harder, Lapis Lazuli or Pyrite?
Pyrite is harder: Mohs 6.5 against Mohs 5.5 for Lapis Lazuli.
Which is more valuable, Lapis Lazuli or Pyrite?
Lapis Lazuli is usually the more valuable of the two: a typical collector specimen runs about $50 against $15 for Pyrite, and premium Lapis Lazuli can reach $500 or more.
