Wavellite

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Wavellite

Wavellite from Poland
General
Category Phosphate mineral
Chemical formula Al3(PO4)2(OH,F)3·5H2O
Identification
Color Green to yellowish-green and yellow, brown, white and colorless
Crystal habit spherical, radial aggregates; striated prisms; crusty to stalactitic
Crystal system Orthorhombic - Dipyramidal
Cleavage [110] Perfect, [101] Good
Fracture Fibrous
Mohs Scale hardness 3.5 - 4
Luster Vitreous to resinous, pearly.
Refractive index nα = 1.518 - 1.535 nβ = 1.524 - 1.543 nγ = 1.544 - 1.561
Optical Properties Biaxial (+)
Birefringence δ = 0.026
Pleochroism Weak
Streak White
Specific gravity 2.3 - 2.4
Diaphaneity Translucent
References [1][2][3]


Wavellite is a phosphate mineral, normally translucent green. It is found in fractures in aluminous metamorphic rock, in hydrothermal regions and in phosphate rock deposits.

Named after William Wavell (?-1829) of England who discovered the mineral in a quarry in Devon, England in 1805. It is found in a wide variety of locations notably in the Mount Ida, Arkansas area in the Ouachita Mountains.

Hydrated aluminium phosphate has the chemical formula:

Al3(PO4)2(OH,F)3·5H2O

[edit] See also

[edit] References

  1. ^ http://rruff.geo.arizona.edu/doclib/hom/wavellite.pdf Mineral Handbook
  2. ^ http://webmineral.com/data/Wavellite.shtml Webmineral
  3. ^ http://www.mindat.org/min-4250.html Mindat