Metabasalt identification and geology

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• Basalt
• Greenschist
• Amphibolite

Sources, scope & corrections

These authoritative resources support category-level nomenclature, terminology, identification methods, and safety. When a specimen-specific safety warning appears, the public-health source listed here directly supports that precaution. They are not line-by-line citations for every other property on this entry, and natural specimens vary.

Editorial owner

GeoMiner

Last updated

2026-03-30T14:39:17.603218+00:00

Review status

Published; not independently peer-reviewed

• Rocks — U.S. National Park Service. Authoritative overview of rock groups, the rock cycle, and geologic processes.
• Can you identify my rock or mineral? — U.S. Geological Survey. Identification limitations and routes to in-person professional verification.

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Common questions

What is Metabasalt?

Low to medium grade metamorphosed basalt retaining some original volcanic texture but with new metamorphic minerals.

How can you identify Metabasalt?

Compare several properties rather than relying on colour alone. This entry records rock type: Metamorphic; texture: Variable, relict igneous texture; grain size: Fine to medium; common minerals: Chlorite, Epidote, Actinolite, Albite, Pumpellyite. Confirm an important identification with additional field tests or qualified laboratory work.

How does Metabasalt form?

Forms from regional or ocean-floor metamorphism of basaltic rocks at varying grades.

Where is Metabasalt commonly found?

Found in greenstone belts, ophiolites, and oceanic crust metamorphic sequences.

What is Metabasalt commonly confused with?

Metabasalt may be confused with Basalt, Greenschist, Amphibolite. Compare multiple diagnostic properties because colour and surface appearance can overlap.