Comparison · Igneous Rocks
Granite vs Monzonite
Granite and Monzonite 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 Monzonite
- Both sit near Mohs 6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Streak color differs: Granite leaves a variable; test individual minerals streak on unglazed porcelain, Monzonite leaves variable; usually light gray.
- Luster is different: Granite is vitreous while Monzonite is dull.
- They overlap in pink, gray, white, and black, but Monzonite also comes in green.
Granite vs Monzonite properties
| Property | Granite | Monzonite |
|---|---|---|
| Type | Igneous Rocks | Igneous Rocks |
| Mohs hardness | 6.5 | 6 |
| Luster | vitreous | dull |
| Streak | Variable; test individual minerals | Variable; usually light gray |
| Transparency | opaque | opaque |
| Specific gravity | 2.7 | 2.75 |
| Crystal system | varies | varies |
| Common colors | Pink, Gray, White, Black | Gray, Pink, White, Black, Greenish gray |
| Rarity | common | common |
| Typical specimen value | $1–$50+ | $1–$75+ |
Which is more valuable?
Typical specimens of Granite and Monzonite 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 Monzonite
Monzonite is a coarse-grained intrusive igneous rock with roughly balanced alkali feldspar and plagioclase and little quartz. It can resemble granite or diorite in hand sample.
Granite vs Monzonite FAQ
Is Granite the same as Monzonite?
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 Monzonite?
Both sit near Mohs 6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Streak color differs: Granite leaves a variable; test individual minerals streak on unglazed porcelain, Monzonite leaves variable; usually light gray. Luster is different: Granite is vitreous while Monzonite is dull.
Which is harder, Granite or Monzonite?
Granite is harder: Mohs 6.5 against Mohs 6 for Monzonite.
Which is more valuable, Granite or Monzonite?
Typical specimens of Granite and Monzonite trade in a similar range, around $10.
