Hornblendite identification and geology

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• Pyroxenite
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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

2026-03-30T14:39:31.608959+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 Hornblendite?

Dark ultramafic rock composed almost entirely of hornblende amphibole. Uncommon but found in some plutonic complexes.

How can you identify Hornblendite?

Compare several properties rather than relying on colour alone. This entry records rock type: Igneous Intrusive; texture: Phaneritic; grain size: Coarse; common minerals: Hornblende 90%, Biotite, Magnetite. Confirm an important identification with additional field tests or qualified laboratory work.

How does Hornblendite form?

Forms as cumulate layers in mafic-ultramafic intrusions or from crystallization of water-rich mafic magmas.

Where is Hornblendite commonly found?

Found in mafic-ultramafic plutonic complexes worldwide.

What is Hornblendite commonly confused with?

Hornblendite may be confused with Pyroxenite, Amphibolite, Gabbro. Compare multiple diagnostic properties because colour and surface appearance can overlap.