Comparison · Igneous Rocks
Granite vs Granodiorite
Granite and Granodiorite are easy to confuse because both are igneous rocks. Both sit near Mohs 6.5, 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 Granite and Granodiorite
- Both sit near Mohs 6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Hold a thin edge to the light: Granite is opaque, Granodiorite is Opaque.
- They overlap in pink, gray, and white, but Granite also comes in black.
Granite vs Granodiorite properties
| Property | Granite | Granodiorite |
|---|---|---|
| Type | Igneous Rocks | Igneous Rocks |
| Mohs hardness | 6.5 | 6–7 |
| Luster | vitreous | Vitreous to dull (mixed mineral grains) |
| Streak | Variable; test individual minerals | — |
| Transparency | opaque | Opaque |
| Specific gravity | 2.7 | 2.65–2.73 |
| Crystal system | varies | — |
| Common colors | Pink, Gray, White, Black | Light gray, Gray, Pinkish gray, White with dark specks |
| Rarity | common | common |
| Typical specimen value | $1–$50+ | $1–$75+ |
Which is more valuable?
Typical specimens of Granite and Granodiorite trade in a similar range, around $10.
About Granite
Granite is a coarse-grained igneous rock composed mainly of quartz, feldspar, and mica. It's one of the most common rocks in Earth's continental crust.
About Granodiorite
Granodiorite is a coarse-grained intrusive igneous rock compositionally between granite and diorite, containing more plagioclase feldspar than orthoclase feldspar along with quartz, biotite, and hornblende. It crystallizes slowly deep underground, allowing individual mineral grains to grow large enough to see without magnification. Granodiorite makes up a substantial portion of the continental crust and forms the core of many mountain ranges worldwide, including much of the Sierra Nevada batholith.
Granite vs Granodiorite FAQ
Is Granite the same as Granodiorite?
No. Both are igneous rocks, but they are distinct rock types with different hardness, streak or luster. Both sit near Mohs 6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Granite from Granodiorite?
Both sit near Mohs 6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Hold a thin edge to the light: Granite is opaque, Granodiorite is Opaque. They overlap in pink, gray, and white, but Granite also comes in black.
Which is harder, Granite or Granodiorite?
They are about equally hard, both near Mohs 6.5.
Which is more valuable, Granite or Granodiorite?
Typical specimens of Granite and Granodiorite trade in a similar range, around $10.
