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Basanite identification and geology

Basanite rock reference specimen

Olivine-bearing alkaline volcanic rock similar to tephrite but with significant olivine. Rich in feldspathoids. Texture: Porphyritic to aphanitic. Rock type: Igneous Extrusive. Grain size: Fine. Minerals present: Olivine, Augite, Plagioclase, Nepheline. Formation: Erupts from alkaline mafic volcanism in continental rifts and intraplate settings. Common geological settings: East African Rift, Germany Eifel , Canary Islands; found in continental rift volcanics. Common look-alikes and related entries: Basalt, Tephrite, Nephelinite.

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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
2026-03-30T14:38:16.979892+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 Basanite?
Olivine-bearing alkaline volcanic rock similar to tephrite but with significant olivine. Rich in feldspathoids.
How can you identify Basanite?
Compare several properties rather than relying on colour alone. This entry records rock type: Igneous Extrusive; texture: Porphyritic to aphanitic; grain size: Fine; common minerals: Olivine, Augite, Plagioclase, Nepheline. Confirm an important identification with additional field tests or qualified laboratory work.
How does Basanite form?
Erupts from alkaline mafic volcanism in continental rifts and intraplate settings.
Where is Basanite commonly found?
East African Rift, Germany Eifel , Canary Islands; found in continental rift volcanics.
What is Basanite commonly confused with?
Basanite may be confused with Basalt, Tephrite, Nephelinite. Compare multiple diagnostic properties because colour and surface appearance can overlap.

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