Comparison · Metamorphic Rocks
Greenschist vs Serpentinite
Greenschist and Serpentinite are easy to confuse because both are metamorphic rocks. Greenschist is harder (Mohs 4.5) than Serpentinite (Mohs 2.5–4), so Greenschist will scratch Serpentinite and not the other way round. A copper coin (Mohs 3.5) scratches it, but a fingernail does not. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Greenschist and Serpentinite
- Greenschist is harder (Mohs 4.5) than Serpentinite (Mohs 2.5–4), so Greenschist will scratch Serpentinite and not the other way round. A copper coin (Mohs 3.5) scratches it, but a fingernail does not.
- Streak color differs: Greenschist leaves a variable; usually pale greenish gray streak on unglazed porcelain, Serpentinite leaves white.
- Hold a thin edge to the light: Greenschist is opaque, Serpentinite is Opaque, translucent in thin splinters.
- They overlap in green and black, but Greenschist also comes in gray and white and Serpentinite also comes in yellow and multicolored.
Greenschist vs Serpentinite properties
| Property | Greenschist | Serpentinite |
|---|---|---|
| Type | Metamorphic Rocks | Metamorphic Rocks |
| Mohs hardness | 4.5 | 2.5–4 |
| Luster | silky | Greasy, waxy, silky |
| Streak | Variable; usually pale greenish gray | White |
| Transparency | opaque | Opaque, translucent in thin splinters |
| Specific gravity | 2.9 | 2.5–2.6 |
| Crystal system | varies | — |
| Common colors | Green, Gray green, Dark green, Black, White | Green, Dark green, Yellowish green, Mottled green and black |
| Rarity | common | common |
| Typical specimen value | $1–$75+ | $1–$75+ |
Which is more valuable?
Typical specimens of Greenschist and Serpentinite trade in a similar range, around $10.
About Greenschist
Greenschist is a greenish metamorphic rock named for its common green minerals and schistose texture. It often looks green, gray-green, or dark green and may have a silky sheen.
About Serpentinite
Serpentinite is a metamorphic rock composed largely of serpentine group minerals, chiefly antigorite, chrysotile, and lizardite, formed through the hydrothermal alteration of olivine-rich ultramafic rock. The reaction, called serpentinization, occurs when water reacts with peridotite or dunite at moderate temperatures, releasing heat and hydrogen while transforming the rock's mineralogy and texture. Its mottled green surface, often resembling snakeskin, gives the rock its name.
Greenschist vs Serpentinite FAQ
Is Greenschist the same as Serpentinite?
No. Both are metamorphic rocks, but they are distinct rock types with different hardness, streak or luster. Greenschist is harder (Mohs 4.5) than Serpentinite (Mohs 2.5–4), so Greenschist will scratch Serpentinite and not the other way round. A copper coin (Mohs 3.5) scratches it, but a fingernail does not.
How can you tell Greenschist from Serpentinite?
Greenschist is harder (Mohs 4.5) than Serpentinite (Mohs 2.5–4), so Greenschist will scratch Serpentinite and not the other way round. A copper coin (Mohs 3.5) scratches it, but a fingernail does not. Streak color differs: Greenschist leaves a variable; usually pale greenish gray streak on unglazed porcelain, Serpentinite leaves white. Hold a thin edge to the light: Greenschist is opaque, Serpentinite is Opaque, translucent in thin splinters.
Which is harder, Greenschist or Serpentinite?
Greenschist is harder: Mohs 4.5 against Mohs 2.5–4 for Serpentinite.
Which is more valuable, Greenschist or Serpentinite?
Typical specimens of Greenschist and Serpentinite trade in a similar range, around $10.
