Leightonite

Formation of Leightonite

It was first described in 1938 for an occurrence in the Chuquicamata Mine, Colama, El Loa Province, Antofagasta Region, Chile, and named in honor of Tomas Leighton Donoso (1896–1967), Professor of Mineralogy at the University of Santiago, Chile. It occurs in alkali oxidized zones of copper deposits and is associated with natrochalcite, blodite, atacamite, bellingerite, kröhnkite, gypsum and quartz in the discovery location at Chuquicamata, Chile, along with chalcanthite, anhydrite and lammerite in Tsumeb, Namibia. It has also been reported from the Schwaz area of North Tyrol, Austria, and the Visdalen Soapstone Quarry, Lom, Norway. At the mining site of Chuquicamata, Chile, Leightonite is not found in rich ore; rather it only appears in borderland material within 50 m (160 ft) of the surface, acting as a cement between rock fragments as it fills in cracks and cross-fiber veins in surfaces as a network of crystals. Although a hydrous sulfate of copper, it is not a major source of the element. Because of its rare nature, it is valued by mineral collectors.