Crandallite
Species
Rare · CaAl₃(PO₄)(PO₃OH)(OH)₆
A calcium aluminium phosphate that forms where phosphate rock weathers, usually as dull white crusts and nodules rather than crystals. It is a quiet but widespread part of the phosphate cycle.
Identity
- Formula
- CaAl₃(PO₄)(PO₃OH)(OH)₆
- Chemical class
- Phosphate
Crystallography
- Crystal system
- Trigonal
- Habits
- Botryoidal, Massive, Earthy, Fibrous
Physical properties
- Mohs hardness
- 5
- Density
- 2.84 g/cm³
- Luster
- Dull, Vitreous
- Colors
- gray, yellow, white
- Streak
- white
- Transparency
- Translucent, Opaque
Geology
- Origins
- Sedimentary, Hydrothermal
- Host rocks
- Granite, Limestone and chalk
- Associated minerals
- Apatite, Wavellite, Quartz
- Found in
- Pegmatite deposit
- Geography
- USA, Brazil, Australia
Classification
- Rarity
- Rare
- 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, Crandallite. Mineral Data Publishing, Handbook of Mineralogy, 2001.
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