igneous

Indigo Gabbro

Gabbro (composed of plagioclase feldspar, pyroxene, and olivine)

Hardness: 6-7 (Mohs scale); Color: Black, charcoal gray, with indigo/purple or blue-green spots; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained); Specific gravity: 2.7–3.3

Hardness: 6-7 (Mohs scale)
Color: Black, charcoal gray, with indigo/purple or blue-green spots
Luster: Vitreous to dull

Identified May 18, 2026More igneous →

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Physical properties

Hardness: 6-7 (Mohs scale); Color: Black, charcoal gray, with indigo/purple or blue-green spots; Luster: Vitreous to dull; Crystal structure: Phaneritic (coarse-grained); Specific gravity: 2.7–3.3

Formation & geological history

Formed through the slow cooling of magnesium-rich and iron-rich magma beneath the Earth's surface. This specific variety is primarily sourced from Madagascar and dates back to the Precambrian era.

Uses & applications

Primarily used as a decorative stone, in lapidary work for making points and spheres, and very popular in metaphysical or spiritual communities.

Geological facts

Also known commercially as Mystic Merlinite. While technically a gabbro, its unique color palette comes from the specific combination of coarse-grained minerals including amphibole and quartz inclusions.

Field identification & locations

Identify by its heavy weight (high density), lack of quartz transparency, and characteristic 'flecked' or 'orbicular' patterns of lighter colors against a dark background. Commonly found in Madagascar.

Other igneous specimens

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Blue Apatite

Fluorapatite (Ca5(PO4)3F)

mineral

Dark Igneous Rock (Likely Basalt or Diabase)

Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.

Igneous

Magnetite

Iron(II,III) oxide (Fe3O4)

mineral

Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

mineral

Blue Apatite

Apatite (Group), Ca5(PO4)3(F,Cl,OH)

mineral

Magnetite

Magnetite (Fe3O4)

mineral