Title
leightonite
Composition
K2Ca2Cu2+(SO4)4·2H2O
Crystal System
Triclinic
Status at Tsumeb
Confirmed
Abundance
Extremely rare
Distribution
Second oxidation zone.
Paragenesis
Supergene.
Type Locality
No
Entry Type
Species TSNB209
General Notes
Leightonite is part of an unusual paragenesis discovered in the North-East Stope on 35 Level in the second oxidation zone in January 1980. Leightonite crystals (to 1 mm) are associated with anhydrite, chalcanthite, lammerite, and ferroan thometzekite (Keller 1981; Keller and Bartelke 1982; Gebhard 1999).
Keller and Bartelke (1982) proposed the following paragenesis:
R/7: primary sulphides >> chalcocite >> lammerite >> unidentified silicates >> TK-like mineral [thometzekite] >> anhydrite >> leightonite >> chalcanthite >> gypsum
Leightonite presents as white to very pale green pseudo-orthorhombic crystals, elongated on [001]. It is associated with anhydrite and the two minerals are readily confused; however, the perfect cleavage of anhydrite distinguishes it from leightonite (Keller and Bartelke 1982).
Associated Minerals
anhydrite; chalcanthite; chalcocite; gypsum; lammerite; thometzekite
