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Anapaite

Anapaite
Anapaite.jpg
Anapaite from Ukraine
General
Category Phosphate minerals
Formula
(repeating unit)
Ca2Fe2+(PO4)2·4H2O
Strunz classification 8.CH.10
Crystal system Triclinic
Crystal class Pinacoidal (1)
Space group Triclinic
H-M symbol: (1)
Space group: P1
Unit cell a = 6.447, b = 6.816
c = 5.898 [Å]; α = 101.64°
β = 104.24°, γ = 70.76°; Z = 1
Identification
Color Green, greenish white to colorless
Crystal habit Tabular to bladed crystals, radiating clusters, incrustations, fibrous, and in nodules
Cleavage Perfect on {001}, distinct on {010}
Tenacity Flexible
Mohs scale hardness 3.5
Luster Vitreous
Streak White
Diaphaneity Transparent
Specific gravity 2.8
Optical properties Biaxial (+)
Refractive index nα=1.602, nβ=1.613, nγ=1.649
Birefringence δ = 0.047
Pleochroism Not visible
2V angle Measured: 52° to 56°
References

Anapaite is a calciumiron phosphate mineral with formula: Ca2Fe2+(PO4)2·4H2O. It is a mineral that typically occurs in cavities in fossil bearing sedimentary rocks. It is also found in phosphate bearing iron ores and rarely in pegmatites. It is commonly found with goethite, siderite and vivianite.

It was named after the type locality on the Black Sea coastal region of Anapa, Taman Peninsula, Russia. Noted localities include Kertch (Crimea, Ukraine) and Bellver de Cerdanya (Girona, Catalonia, Spain).


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