Supergene mineralogy of the Lojane Sb-As-Cr deposit, Republic of Macedonia - Tracing the mobilisation of toxic metals

Autor(en)

Uwe Kolitsch, Tamara Đorđević, Goran Tasev, Todor Serafimovski, Ivan Boev, Blazo Boev

Abstrakt

As part of a larger project on the environmental mineralogy and geochemistry of the Lojane Sb-As-Cr deposit, Republic of Macedonia, which was mined for chromite and, later, stibnite until 1979 and is a substantial source of arsenic and antimony pollution, the supergene mineralogy of the deposit was studied. Samples collected on ore and waste dumps were used to identify and characterize the previously uninvestigated suite of supergene mineral phases by standard mineralogical techniques. The following species were determined (in alphabetical order): annaber-gite, arseniosiderite(?), gypsum, hexahydrite, hörnesite, pararealgar, roméite-group minerals, rozenite, scorodite, sen-armontite, stibiconite, sulphur, tripuhyite and valentinite. Their occurrences are described and their local conditions of formation are discussed. High-resolution Raman spectra of hörnesite, hexahydrite and rozenite are provided and com-pared with literature data. The Mg arsenate hörnesite is by far the most common secondary arsenate (and immobilizer of arsenic), an observation attributed to the Mg- and carbonate-rich serpentinite matrix which buffers any acid weath-ering solutions. Antimony is efficiently immobilized in secondary Sb(III) oxides, but trace amounts are also incorpo-rated into scorodite. Nickel, derived from primary Ni(-bearing) sulphide and sulpharsenide minerals, is mobilized and incorporated into annabergite and chemically variable roméite-group minerals. No mobilization of Cr was noted, in agreement with literature data on weathered Cr deposits.

Organisation(en)

Institut für Mineralogie und Kristallographie

Externe Organisation(en)

Goce Delčev University of Štip, Naturhistorisches Museum Wien (NHM)

Journal

Geologica Macedonica

Band

32

Seiten

95-117

Anzahl der Seiten

24

ISSN

1857-8586

Publikationsdatum

12-2018

Peer-reviewed

Ja

ÖFOS 2012

105116 Mineralogie, 105906 Umweltgeowissenschaften

Schlagwörter

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/a606a645-21db-472f-97e6-a29863f47dd1