Dark orange microcrystals of the very rare mineral chlorbartonite from the type locality (Koashva Open Pit, Khibiny Massif, Kola, Russian Federation) and only one of the five known localities worldwide. Chlorbartonite is one of the very few sulphides containing the alkali metal potassium and the halogen chlorine. — Photo: David Hospital · CC BY-SA 4.0
Chlorbartonite
Chlorbartonite is an IMA-recognized mineral species in the sulfide class, with the chemical formula K₆Fe₂₄S₂₆Cl.
It crystallizes in the tetragonal crystal system (space group I4/mmm). It is a member of the Djerfisherite structural group.
Key properties: Mohs hardness 4; specific gravity 3.7; Black streak; Submetallic luster.
IMA symbol Cbtn, IMA status: approved, named in 2000.
Found in an alkaline hydrothermal vein in feldspathic urtite within apatite-nepheline rock.
It is found associated with Djerfisherite, rasvumite, microcline, pectolite, sodalite, aegirine.
A prefix, chlor, indicates the chlorine-dominant analog of bartonite.