What is Wavellite?
Wavellite is a hydrated aluminium phosphate famous for green radial sprays and botryoidal crusts, especially from phosphate-rich cavities and weathered rocks.
Mineralogy and structure
Reference formula: Al3(PO4)2(OH,F)3·5H2O. Wavellite is orthorhombic and can contain fluorine in the hydroxyl sites. COD 9008143 provides an exact structural reference; colour and hydration can vary in natural material. Wavellite is classified with phosphates and has orthorhombic crystal symmetry. Typical hardness is 3–4 on the Mohs scale and specific gravity is approximately 2.3–2.4.
Colour, lustre and habit
Typical colours include green, blue-green, yellow-green, white, colourless. The usual radiating, spherical, crusty habit and vitreous, pearly, silky lustre help describe a specimen, but colour alone is not diagnostic.
Formation and notable localities
Wavellite forms in or is associated with phosphate-rich cavities, weathered aluminium-bearing rocks, hydrothermal veins and mine dumps. Important documented localities include Arkansas in the United States, England, Bolivia, Brazil, Germany and Australia.
Green radial sprays made for the cabinet
Wavellite is a strong collector and sales mineral because its green colour, radiating geometry and natural botryoidal surface make every good specimen look intentional.
Collecting and care
Soft and hydrated: avoid soaking, acids and abrasion; support radial sprays and clean only with gentle dry or barely damp methods.
