Wavellite
Species
Uncommon · Al₃(PO₄)₂(OH)₃·5H₂O
Aluminium phosphate hydroxide forming distinctive radial wheel-like aggregates visible in cross-section. Found in low-grade metamorphic and hydrothermal environments. The best material comes from Arkansas, where it fills joints in chert.
Identity
- Formula
- Al₃(PO₄)₂(OH)₃·5H₂O
- Chemical class
- Phosphate
Crystallography
- Crystal system
- Orthorhombic
- Habits
- Acicular, Massive, Fibrous
- Fracture
- Subconchoidal
Physical properties
- Mohs hardness
- 3.5
- Density
- 2.36 g/cm³
- Luster
- Vitreous, Resinous
- Colors
- yellow-green, green, white, colorless
- Streak
- white
- Transparency
- Translucent
Geology
- Origins
- Sedimentary, Hydrothermal
- Host rocks
- Schist and gneiss, Limestone and chalk
- Associated minerals
- Crandallite, variscite
- Geography
- USA (Arkansas), UK, Germany, Bolivia, Czech Republic
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, Wavellite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
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