Secondary phases from the alteration of a pile of zinc-smelting slag as indicators of environmental conditions: an example from Świętochłowice, Upper Silesia, Poland (original) (raw)

The Canadian Mineralogist

Slags produced by the pyrometallurgical treatment of Zn ore, deposited at the dump in Świętochłowice, in Upper Silesia, southern Poland, are dominated by synthetic analogues of olivine, melilite, pyroxene, feldspars, willemite, zincite and spinel, occurring in various assemblages. Secondary phases either formed at high-temperature or due to weathering are both common at the pile. They include efflorescences of gypsum, epsomite, hexahydrite and bianchite, encrustations of gypsum, anglesite and cerussite, and accumulations of jarosite, goethite and hematite. Two groups are identified: the first one, where sulfates are dominant, is ubiquitous; the second one, of local importance, has originated under conditions varying significantly from one place to another. The weathered phases originate during episodic outflow of water from the pile after rainfall. These mineralogical data and leaching experiments show that, among the primary phases, zincite is most readily weathered, followed by willemite, melilite and the spinel-group phases.