Fluellite

fluellite

crandallite

variscite

wavellite

Images

Formula:Al2(PO4)F2(OH).7H2O
Hydrated phosphate containing halogen
Crystal System: Orthorhombic
Specific gravity: 2.139 to 2.17 measured, 2.29 calculated
Hardness: 3
Streak: White
Colour: Colourless, white, yellow
Environments

Pegmatites

Fluellite is a rare secondary mineral, formed by weathering of earlier phosphates in some complex granite pegmatites. Associated minerals include fluorapatite, wavellite, phosphosiderite, strengite, aldermanite, cacoxenite, variscite, turquoise, fluorite and quartz (HOM).

Localities

In the phosphate deposits of South Australia, fluellite is abundant. At St John's quarry it occurs as isolated crystals associated with wavellite and minyulite. At Moculta and Tom's quarry it can be partially or totally replaced by aldermanite, crandallite or perhamite (AJM 17.1.16).

At the Königswart mine, Schönegründ, Baiersbronn, Freudenstadt, Karlsruhe, Baden-Württemberg, Germany, fluellite occurs as an alteration product of triplite (Dana).

At Hagendorf, Waidhaus, Neustadt an der Waldnaab, Upper Palatinate, Bavaria, Germany fluellite occurs with phosphosiderite and strengite (Dana).

At the type locality, the Stenna Gwyn mine, Foxhole, St Stephen-in-Brannel, Cornwall, England, UK, fluellite occurs as minute crystals on quartz associated with fluorite, arsenopyrite, torbernite and wavellite (Dana, Mindat)>

Back to Minerals