Löllingite

Löllingite, also known as Loellingite is an iron arsenide mineral with formula FeAs₂. It is often found associated with arsenopyrite (FeAsS) from which it is hard to distinguish. Cobalt, nickel and sulfur substitute in the structure. The orthorhombic lollingite group includes the nickel iron arsenide rammelsbergite and the cobalt iron arsenide safflorite.

It forms opaque silvery white orthorhombic prismatic crystals often exhibiting crystal twinning. It also occurs in anhedral masses and tarnishes on exposure to air. It has a Mohs hardness of 5.5 to 6 and a quite high specific gravity of 7.1 to 7.5. It becomes magnetic after heating.

Löllingite was first described in 1845 at the Lölling district in Carinthia, Austria. It is known by a number of synonyms including leucopyrite.

References

* Mindat
* Webmineral
* Mineral galleries
* Minerals of Franklin, N.J.


List of minerals