metamorphic

Eclogite

Eclogite (Omphacite-Garnet Metamorphic Rock)

AI-generated identification · may be incorrect

Hardness: 6-7 (Mohs); Color: Mottled red (garnet) and green (omphacite pyroxene); Luster: Vitreous to dull; Crystal structure: Coarse-grained granular; Specific gravity: 3.2-3.6 (very dense)

Hardness: 6-7 (Mohs)
Color: Mottled red (garnet) and green (omphacite pyroxene)
Luster: Vitreous to dull

Identified July 4, 2026More metamorphic →

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Physical properties

Hardness: 6-7 (Mohs); Color: Mottled red (garnet) and green (omphacite pyroxene); Luster: Vitreous to dull; Crystal structure: Coarse-grained granular; Specific gravity: 3.2-3.6 (very dense)

Formation & geological history

Formed under extreme high-pressure and moderate-to-high temperature conditions in subduction zones or the lower crust/upper mantle. It represents the metamorphism of basaltic rock at depths exceeding 45km.

Uses & applications

Primarily of interest to researchers and collectors; occasionally used as a decorative stone or for heavy-duty construction aggregate due to high density.

Geological facts

Eclogite is often called the 'Christmas Tree Rock' because of its striking red and green coloration. It is a key indicator of deep-seated tectonic processes.

Field identification & locations

Identified by the distinct combination of deep red almandine-pyrope garnets and green omphacite pyroxene. It is unusually heavy for its size. Often found in glaciated regions or specific metamorphic terranes like the Alps or Norway.