Comparison · Igneous Rocks
Andesite vs Kimberlite
Andesite and Kimberlite are easy to confuse because both are igneous rocks. Both sit near Mohs 5–6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Andesite and Kimberlite
- Both sit near Mohs 5–6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- They overlap in gray and green, but Andesite also comes in brown and black and Kimberlite also comes in blue and yellow.
Andesite vs Kimberlite properties
| Property | Andesite | Kimberlite |
|---|---|---|
| Type | Igneous Rocks | Igneous Rocks |
| Mohs hardness | 5–6 | 5–6.5 |
| Luster | Dull groundmass with vitreous phenocrysts | Dull to vitreous |
| Transparency | Opaque | Opaque |
| Specific gravity | 2.5–2.8 | 2.5–2.9 |
| Common colors | Gray, Dark gray, Greenish gray, Brown, Black | Blue-gray ('blue ground'), Yellow ('yellow ground', weathered), Dark green, Gray |
| Rarity | common | common |
| Typical specimen value | $1–$75+ | $1–$75+ |
Which is more valuable?
Typical specimens of Andesite and Kimberlite trade in a similar range, around $10.
About Andesite
Andesite is a fine-grained, intermediate volcanic rock formed from lava with a silica content between basalt and rhyolite, typically 57 to 63 percent. It is named for the Andes Mountains, where it makes up much of the volcanic arc, and its groundmass is usually too fine to identify individual minerals without magnification. Andesite forms at convergent plate boundaries where oceanic crust melts beneath continental or island arcs.
About Kimberlite
Kimberlite is a rare, ultramafic igneous rock famous as the primary source rock for natural diamonds. It originates from partial melting deep in Earth's mantle, often more than one hundred fifty kilometers down, and erupts violently through narrow, carrot-shaped volcanic pipes. Named after Kimberley, South Africa, where major diamond-bearing pipes were first mined, it is a chaotic mixture of olivine, mica, and fragments picked up from surrounding rock on its way to the surface.
Andesite vs Kimberlite FAQ
Is Andesite the same as Kimberlite?
No. Both are igneous rocks, but they are distinct rock types with different hardness, streak or luster. Both sit near Mohs 5–6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Andesite from Kimberlite?
Both sit near Mohs 5–6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. They overlap in gray and green, but Andesite also comes in brown and black and Kimberlite also comes in blue and yellow.
Which is harder, Andesite or Kimberlite?
They are about equally hard, both near Mohs 5–6.
Which is more valuable, Andesite or Kimberlite?
Typical specimens of Andesite and Kimberlite trade in a similar range, around $10.
