Challacolloite

challacolloite

caracoite

cotunnite

boleite

Images

Formula: KPb2Cl5
Anhydrous chloride
Crystal System: Monoclinic
Specific gravity: 4.77 calculated
Hardness: 2 to 3
Streak: White
Colour: Colourless to white
Luminescence: Not fluorescent under UV
Solubility: Soluble in water
Environments

Hydrothermal environments
Fumeroles

Localities

At the type locality, the Lolón Main Mine, Cerro Challacollo, Pozo Almonte, Tamarugal Province, Tarapacá, Chile, challacolloite occurs as a hydrothermal mineral in the epithermal vein-type silver deposit, intergrown with cotunnite and a mixture of boleite and pseudoboleite in aggregates up to 4 mm in size comprised of subparallel intergrowths of bent lamellae, 25 µm in width, 50 µm in length. It is also associated with hemimorphite, caracolite, anglesite, nitratine, anhydrite and fluorite in quartz vugs. The challacolloite is a product of fumarole activity, on cavernous leucite-tephritic lava (AM 91.8.1452-1453, HOM).
Challacolloite from the Lolón Main Mine - Image

At Mount Vesuvius, Metropolitan City of Naples, Campania, Italy, challacolloite is found as a sublimate near volcanic fumaroles, associated with cotunnite as a crust, and as botryoidal aggregates in a leucite-tephritic lava. The aggregates are comprised of subparallel intergrowths of bent lamellae, 25 µm in width and 50 µm in length. Associated minerals include cotunnite, boleite, pseudoboleite, hemimorphite, caracolite, anglesite, nitratine, anhydrite and fluorite (AM 91.8.1452-1453, HOM).
Challacolloite from Vesuvius - Image

Back to Minerals