(TL) indicates type locality. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
Ettler, V., Johan, Z., Kříbek, B., Šebek, O. & Mihaljevič, M. (2009): Mineralogy and environmental stability of slags from the Tsumeb smelter, Namibia. Applied Geochemistry 24, 1-15.