Comparison · Igneous Rocks
Gabbro vs Larvikite
Gabbro and Larvikite are easy to confuse because both are igneous rocks. Both sit near Mohs 5–6.5, 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 Gabbro and Larvikite
- Both sit near Mohs 5–6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Hold a thin edge to the light: Gabbro is Opaque, Larvikite is opaque.
- They overlap in gray, black, and white, but Gabbro also comes in green and multicolored and Larvikite also comes in blue.
Gabbro vs Larvikite properties
| Property | Gabbro | Larvikite |
|---|---|---|
| Type | Igneous Rocks | Igneous Rocks |
| Mohs hardness | 5–6.5 | 6 |
| Luster | Dull to vitreous (in crystals) | vitreous |
| Streak | — | White to light gray |
| Transparency | Opaque | opaque |
| Specific gravity | 2.9–3.1 | 2.75 |
| Crystal system | — | varies |
| Common colors | Dark gray, Black, Greenish black, Speckled black and white | Dark gray, Blue gray, Black, Silver blue, White |
| Rarity | common | common |
| Typical specimen value | $1–$75+ | $5–$300+ |
Which is more valuable?
Larvikite is usually the more valuable of the two: a typical collector specimen runs about $40 against $10 for Gabbro, and premium Larvikite can reach $300 or more.
About Gabbro
Gabbro is a coarse-grained, dark-colored intrusive igneous rock composed mainly of calcium-rich plagioclase feldspar and pyroxene, with the plutonic equivalent of basalt. It forms deep underground where mafic magma cools slowly enough for its mineral grains to grow large and interlock visibly. Its dense, speckled black-and-white texture makes it a popular dimension stone sold commercially as black granite.
About Larvikite
Larvikite is a feldspar-rich igneous rock famous for blue-silver flashes from feldspar crystals. It is often sold as decorative stone and can be confused with labradorite-bearing rocks.
Gabbro vs Larvikite FAQ
Is Gabbro the same as Larvikite?
No. Both are igneous rocks, but they are distinct rock types with different hardness, streak or luster. Both sit near Mohs 5–6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Gabbro from Larvikite?
Both sit near Mohs 5–6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Hold a thin edge to the light: Gabbro is Opaque, Larvikite is opaque. They overlap in gray, black, and white, but Gabbro also comes in green and multicolored and Larvikite also comes in blue.
Which is harder, Gabbro or Larvikite?
They are about equally hard, both near Mohs 5–6.5.
Which is more valuable, Gabbro or Larvikite?
Larvikite is usually the more valuable of the two: a typical collector specimen runs about $40 against $10 for Gabbro, and premium Larvikite can reach $300 or more.
