SAFFLORITE

    Class : Sulfides and sulfosalts
    Subclass : Arsenides
    Crystal system : Orthorhombic
    Chemistry : CoAs2
    Rarity : Uncommon


Safflorite is one of the "white arsenides", a generic term grouping together cubic and monoclinic cobalt or nickel arsenides (skutterudite and rammelsbergite). It is found in medium-temperature hydrothermal veins associated in particular with other cobalt and nickel arsenides and native bismuth. Above 800°C, safflorite forms two complete solid solutions, one with löllingite, the other with rammelsbergite, solid solutions that become partial at low temperature. Its name comes from the German safflor or zaffer (dye product) in allusion to its use as a blue pigment. With a metallic luster and a tin-white color, safflorite generally occurs in fibrous to fibroradiated masses. Clear crystals of appreciable size are very rare, with a prismatic appearance, reminiscent of arsenopyrite. Microscopic crystals are often twinned in very characteristic structures forming 6-pointed stars. At outcrops, safflorite alters into different arsenates.

Main photo : Safflorite from Neuglück Mine, Germany © Michael Förch

Safflorite from Neuglück Mine, Garmany © Sephan Wolfsried
Twinned safflorite section from Schneeberg, Germany © Günter Grundmann
Twinned safflorite from Oumlil Mine, Morocco © OT. Ljøstad
Safflorite de Langis Mine, Ontario, Canada © Rob Lavinsky

Safflorite in the World

The best crystals of safflorite are centimetric, squat and flattened and come from Tunaberg (Sweden). Beautiful crystals have also been discovered in Bieber (Hesse, Germany) in the Ni-Co-Bi-Ag-U veins of Schneeberg and Annaberg (Saxony), and especially in the large cobalt mine of Bou Azzer (Morocco). It also exists in many other mines, notably in Germany, Australia (Broken Hill), Italy (Monte Narba, Sardinia) and Canada.

Safflorite in France

In France, safflorite is known at Chalanches (Isère), Ste-Marie-aux-Mines (Haut-Rhin), Bussang (Vosges) and in the Vallée d'Aure (Hautes-Pyrénées).

Twinning

Twins with 5 individuals are known on {011} and with {101} as composition plane.

Fakes and treatments

No fakes listed for this mineral species.



Hardness : 4.5 to 5
Density : 7.2
Fracture : Irregular to conchoidal
Streak : Gray-black


TP : Opaque
RI : -
Birefringence : -
Optical character : -
Pleochroism : None
Fluorescence : None


Solubility : -

Magnetism : NoneRadioactivity : None