Platinum-group element distribution in base-metal sulfides of the UG2 chromitite, Bushveld Complex, South Africa—a reconnaissance study

Osbahr, Inga; Oberthür, Thomas; Klemd, Reiner; Josties, Anja

doi:10.1007/s00126-014-0538-z

Cited by 53 publications

(24 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The Rh and Pd proportions at Musongati are very similar to e.g. ~20-50% proportions of Pd in pentlandite in the Bushveld Complex (Osbahr et al, 2014) or PGE proportions in other PGE deposits worldwide (Lightfoot & Evans-Lamswood, 2015). These results demonstrate that a significant amount of PGE are hosted by sulfides.…”

Section: Pge Distributionmentioning

confidence: 55%

See 1 more Smart Citation

Platinum group element mineralization at Musongati (Burundi): concentration and Pd-Rh distribution in pentlandite

Paredis¹,

Muchez²,

Dewaele³

2017

Geol. Belg.

View full text Add to dashboard Cite

ABSTRACT. The mafic-ultramafic intrusions of the Karagwe-Ankole belt in Burundi are considered as a new potential source for platinum group elements (PGE). The intrusions have mainly been studied for their PGE potential with regard to PGE concentration, but the mineralogical distribution of PGE has not been examined to the same level. This study focuses on the Pd and Rh distribution in pentlandite of ultramafic rocks of the Musongati layered intrusion. The results are based on whole rock and pentlandite analyses which were incorporated into a mass balance. Palladium proportions in pentlandite vary between 4 and 69%. Rhodium is present in proportions ranging from 1-39% in pentlandite. Other PGE distributions could not be determined in pentlandite due to concentrations below detection limits. The results from this study demonstrate that Pd and Rh are hosted by sulfides since sulfur saturation of the magma occurred early on, perhaps before or simultaneously with the precipitation of silicate minerals. Based on these findings, a preliminary model for the mineralization of PGE in the Musongati intrusion is proposed.KEYWORDS: mafic-ultramafic, layered intrusion, Karagwe-Ankole belt, LA-ICP-MS, NiS FA, pentlandite, mass balance, sulfur saturation.(see further; e.g. Robb, 2005;Kennedy et al., 2013;Kennedy, 2014). A second model is the sulfide fractionation model, which is based on physical and chemical processes where an immiscible sulfide liquid incorporates the major part of PGE (see further; e.g. Dare et al., 2010;Chen et al., 2015). A third, relatively newer model, proposed by e.g. Mungall et al. (2015) is that of flotation of sulfide melt on vapor bubbles, in which the PGE are incorporated during their way up. Knowledge about where and in which phase(s) the PGE occur is, therefore, essential to obtain an insight in the ore-forming processes and hence to assess their recovery from raw materials.In this paper, the results of the investigations for the concentration of PGE in mafic-ultramafic rocks and the Pd and Rh distribution in pentlandite from the Musongati intrusion in Burundi will be discussed. The results are based on whole rock and sulfide phase analyses that were incorporated into a mass balance to calculate the Pd and Rh distribution. Based on these data a preliminary model for the PGE mineralization of the Musongati intrusion is proposed.

show abstract

Section: Pge Distributionmentioning

confidence: 55%

“…where C sul PGE is the concentration of a PGE in a sulfide mineral (as analyzed by LA-ICP-MS) and C wr PGE is the concentration of a PGE in the whole rock (as analyzed by ICP-MS) (Osbahr et al, 2014). The factor 100 is applied to obtain percentages.…”

Section: Pge Concentrationmentioning

confidence: 99%

Platinum group element mineralization at Musongati (Burundi): concentration and Pd-Rh distribution in pentlandite

Paredis¹,

Muchez²,

Dewaele³

2017

Geol. Belg.

View full text Add to dashboard Cite

show abstract

“…20). When pyrite has not been mapped (Djon and Barnes, 2012;Osbahr et al, 2013Osbahr et al, , 2014Smith et al, 2014), pyrite shows a wide range of compositions. This observation could be the result of concentric oscillatory zoning.…”

Section: Comparison With Pyrite From Other Ni-cu-pge Depositsmentioning

confidence: 98%

“…In contrast, the presence of pyrite in magmatic Ni-Cu-PGE deposits is less common. Recent studies have demonstrated that pyrite in these magmatic deposits contain PGE (Oberthür et al, 1997;Barkov et al, 1997;Dare et al, 2011;Djon and Barnes, 2012;Piña et al, 2012Piña et al, , 2013aOsbahr et al, 2013Osbahr et al, , 2014Smith et al, 2014). However, because pyrite is not abundant, very little attention has been paid to the processes that control the distribution of PGE in pyrite.…”

Section: Introductionmentioning

confidence: 95%

Chalcophile and platinum-group element distribution in pyrites from the sulfide-rich pods of the Lac des Iles Pd deposits, Western Ontario, Canada: Implications for post-cumulus re-equilibration of the ore and the use of pyrite compositions in exploration

Duran

Barnes

Corkery³

2015

Journal of Geochemical Exploration

View full text Add to dashboard Cite

“…Base-metal sulfides in the UG-2 chromitite are commonly <1 vol% and comprise pentlandite and chalcopyrite with almost no pyrrhotite present (Osbahr et al 2014).…”

Section: Summary and Comparison With Other Igneous Intrusionsmentioning

confidence: 99%

A study of the trace sulfide mineral assemblages in the Stillwater Complex, Montana, USA

et al. 2016

View full text Add to dashboard Cite

The sulfide assemblages of the Stillwater Complex away from the well-studied ore zones are composed mainly of variable proportions of pyrrhotite, chalcopyrite, pentlandite, and ±pyrite. Excluding vein assemblages and those affected by greenschist and lower temperature alteration, the majority can be classified into two broad assemblages, defined here as pristine (multiphase, often globular in shape) or volatilebearing (multiphase, high-temperature, volatile-rich minerals such as biotite, hornblende, or an unmixed calcite-dolomite assemblage). The volatile-bearing assemblages are mainly found within and below the J-M reef, where native copper and sphalerite are also locally present. Pristine sulfides are found throughout the stratigraphy. Both groups can be affected by apparent S loss in the form of pyrite being converted to magnetite and chalcopyrite to a Cu-Fe-oxide (delafossite), with little to no silicate alteration. An upward trend from pentlandite-rich to pyrrhotite-rich to pyrite-rich assemblages is observed in the footwall rocks in upper GN-I, and the same trend repeats from just below the reef and continues into the overlying N-II and GN-II. Modeling suggests that the sulfide Ni in the Peridotite Zone is largely controlled by silicate Ni. When taken together, observations are most readily explained by the remobilization of selected elements by a hightemperature fluid with the apparent loss of S > Cu > Ni. This could concentrate ore metals by vapor refining, eventually producing a platinum group element-enriched sulfide ore zone, such as the J-M reef.

show abstract

Platinum-group element distribution in base-metal sulfides of the UG2 chromitite, Bushveld Complex, South Africa—a reconnaissance study

Cited by 53 publications

References 18 publications

Platinum group element mineralization at Musongati (Burundi): concentration and Pd-Rh distribution in pentlandite

Platinum group element mineralization at Musongati (Burundi): concentration and Pd-Rh distribution in pentlandite

Chalcophile and platinum-group element distribution in pyrites from the sulfide-rich pods of the Lac des Iles Pd deposits, Western Ontario, Canada: Implications for post-cumulus re-equilibration of the ore and the use of pyrite compositions in exploration

A study of the trace sulfide mineral assemblages in the Stillwater Complex, Montana, USA

Contact Info

Product

Resources

About