RocksdayGranite vs Syenite
How to tell them apart
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
Looks like granite but has little or no quartz; mostly alkali feldspar.
Photo: James St. John, CC BY 2.0
Key differences
- Granite has plenty of glassy quartz.
Side by side
| Property | Granite | Syenite |
|---|---|---|
| Type | Igneous rock | Igneous rock |
| Mohs hardness | 6–7 | 6 |
| Luster | Granular, sparkly | Granular |
| Colors | Pink, Gray, White, Black | Pink, Gray, White |
| Crystal system / structure | Coarse-grained (phaneritic) | Coarse-grained (phaneritic) |
| Specific gravity | 2.63–2.75 | 2.6–2.8 |
| Found in | Sierra Nevada, California; Stone Mountain, Georgia | Magnet Cove, Arkansas; Ontario, Canada |
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 syenite
- Coarse pink or gray feldspar crystals.
- Little or no glassy quartz.
- Some dark hornblende or biotite.
Structure: Coarse-grained (phaneritic)
Full Syenite guide →More comparisons
Could you tell them apart from a blurry close-up?
Play today's Rocksday