RocksdayGranite vs Orbicular Granite
To tell Granite from Orbicular Granite: Granite has no concentric orbs.
A coarse-grained rock that cooled slowly deep underground, made of quartz, feldspar and mica or hornblende.
Photo: The stone gate, CC BY-SA 4.0
Granite full of round, layered orbs of feldspar and darker minerals that grew outward from a core.
Photo: Bachelot Pierre J-P, CC BY-SA 3.0
Key differences
- Granite has no concentric orbs.
Side by side
| Property | Granite | Orbicular Granite |
|---|---|---|
| Type | Igneous rock | Igneous rock |
| Mohs hardness | 6–7 | 6–7 |
| Luster | Granular, sparkly | Granular |
| Colors | Pink, Gray, White, Black | Gray, White, Black, Pink |
| Crystal system / structure | Coarse-grained (phaneritic) | Concentric orbicules in granite |
| Specific gravity | 2.63–2.75 | 2.6–2.8 |
| Found in | Sierra Nevada, California; Stone Mountain, Georgia | Finland; Boogardie, Western Australia |
Properties that are the same for both are grayed out.
How to identify granite
- Speckled with interlocking grains you can see without a lens.
- Glassy gray quartz plus pink or white blocky feldspar.
- Black specks of mica or hornblende.
- Hard, with no layering or banding.
Structure: Coarse-grained (phaneritic)
Full Granite guide →How to identify orbicular granite
- Spherical orbicules with concentric light and dark rings.
- The matrix between orbs is ordinary granite.
- Hard, like granite.
Structure: Concentric orbicules in granite
Full Orbicular Granite guide →More comparisons
Frequently asked questions
What is the difference between granite and orbicular granite?
Granite is an igneous rock with a Mohs hardness of about 6–7 and a granular, sparkly luster, usually pink, gray, white or black. Orbicular Granite is an igneous rock with a Mohs hardness of about 6–7 and a granular luster, usually gray, white, black or pink.
How can you tell granite from orbicular granite?
Granite has no concentric orbs.
Could you tell them apart from a blurry close-up?
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