Cafarsite (Weight: 30.6 g) – Place of discovery: Wanni glacier, Scherbadung area (also Monte Cervandone ), Binn valley, Valais, Switzerland — Photo: Raimond Spekking · CC BY-SA 4.0
Cafarsite
A rare calcium-iron arsenite described in 1966 from Switzerland's Binn Valley.
Intro adapted from Wikipedia (CC BY-SA).
Cafarsite is an IMA-recognized mineral species in the arsenate class, with the chemical formula (Ca,Na, )₁₉Ti₈Fe³⁺₄Fe²⁺₄(AsO₃)₂₈F.
It crystallizes in the cubic crystal system (space group Pn3).
Key properties: Mohs hardness 5.5–6; specific gravity 3.9; Yellow-brown streak; refractive index 2.2; optically isotropic.
IMA symbol Caf, IMA status: approved, named in 1965.
On cleft faces in orthogneiss (Cherbadung, Switzerland).
It is found associated with Asbecasite, gasparite-(Ce), chernovite, synchysite (Cherbadung, Switzerland).
The name refers to elements in the composition, CAlcium, iron (Ferrum), and ARSenic.