igneous
Gabbro (Indigo Gabbro)
Gabbro (mafic intrusive igneous rock)
Hardness: 6-7 (Mohs scale); Color: Black with mottled grey, bluish, or indigo patches; Luster: Vitreous to dull, polished here; Structure: Phaneritic (coarse-grained); Specific Gravity: 2.7-3.3
- Hardness
- 6-7 (Mohs scale)
- Color
- Black with mottled grey, bluish, or indigo patches
- Luster
- Vitreous to dull, polished here
Identified More igneous →
Explore Gabbro (Indigo Gabbro) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6-7 (Mohs scale); Color: Black with mottled grey, bluish, or indigo patches; Luster: Vitreous to dull, polished here; Structure: Phaneritic (coarse-grained); Specific Gravity: 2.7-3.3
Formation & geological history
Formed from the slow cooling of magnesium-rich and iron-rich magma deep beneath the Earth's surface. It is the intrusive equivalent of basalt.
Uses & applications
Commonly used in construction as crushed stone, road base, or dimension stone (granite-like countertops); polished specimens are used as palm stones or in jewelry.
Geological facts
Indigo Gabbro is often marketed under the trade name 'Mystic Merlinite' in metaphysical circles. It is technically a mixture of feldspar, pyroxene, and other dark minerals.
Field identification & locations
Identify by its salt-and-pepper appearance with darker mafic minerals dominating. Found globally in oceanic crust and large intrusive complexes.
