Aegirine
Species
Uncommon · NaFe³⁺Si₂O₆
The sodium iron pyroxene of alkaline rocks, in slender dark green prisms ending in steep points. Named after Ægir, the Norse god of the sea, for the Norwegian syenites where it was first described.
Identity
- Formula
- NaFe³⁺Si₂O₆
- Chemical class
- Silicate
- Mineral group
- Diopside, Enstatite, Hiddenite, Jade, Jadeite, Kunzite
- Also known as
- Acmite
Crystallography
- Crystal system
- Monoclinic
- Habits
- Prismatic, Acicular, Fibrous
- Fracture
- Uneven
Physical properties
- Mohs hardness
- 6
- Density
- 3.52 g/cm³
- Luster
- Resinous, Vitreous
- Colors
- green, greenish black, reddish brown, black
- Streak
- yellowish gray
- Transparency
- Translucent, Opaque
Geology
- Origins
- Igneous, Metamorphic
- Host rocks
- Granite
- Associated minerals
- Nepheline, feldspar, arfvedsonite, eudialyte
- Found in
- Pegmatite deposit
- Geography
- Norway, Russia, Malawi
Classification
- Rarity
- Uncommon
- Gem quality
- No
Sources
- M. Pasero and others, IMA Commission on New Minerals, Nomenclature and Classification, The New IMA List of Minerals, updated September 2026. International Mineralogical Association (CNMNC), 2026.
- J. W. Anthony, R. A. Bideaux, K. W. Bladh, M. C. Nichols, Aegirine. Mineral Data Publishing, Handbook of Mineralogy, 2001.
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