Hanswilkeite

hanswilkeite

rasvumite

srebrodolskite

tilleyite

Images

Formula: KFeS2
Sulphide
Crystal system: Monoclinic
Specific gravity: 2.654 calculated
Hardness: 2
Streak: Brown-black
Colour: Deep purple
Environments

Metamorphic environments

Hanswilkeite is a new mineral, approved in 2022.

Localities

At the type locality, Naẖal Gorer, Tamar Regional Council, Beersheba Subdistrict, Southern District, Israel, hanswilkeite is a potassium-rich natural sulphide discovered in the pyrometamorphic suite of the Hatrurim Formation. It occurs in sulphide-calcite assemblages confined to black-colored calcite-spurrite marbles. It forms single-crystal grains up to 1 mm in size, isometric to lath-like, and often intergrown with less-common rasvumite. Associated minerals include srebrodolskite, tilleyite, fluormayenite, cuspidine, fluorapatite, oldhamite, pyrite and andradite.
Hanswilkeite is the third discovered dithioferrate mineral: a sulfosalt that contains [FeS2] anion with iron in the Fe3+ state. Other known natural dithioferrates are erdite and raguinite. Hanswilkeite has a synthetic counterpart and a group of related synthetic sulphides and selenides, which have been well studied. Hanswilkeite can be considered as an indicator of an extreme potassium-rich environment superimposed onto anhydrous and oxidising formation conditions (AM 110.6.956–965).

Back to Minerals