Fractionation of platinum, palladium, nickel, and copper in sulfide–arsenide systems at magmatic temperature

Helmy, Hassan M.; Ballhaus, Chris; Fonseca, Raúl O. C.; Nagel, T.

doi:10.1007/s00410-013-0951-9

Cited by 62 publications

(30 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…http://www.minsocam.org/ accommodated into MSS nor in the residual sulfide liquid, but were probably incorporated into the arsenide melt.The As content of MSS is constant, around 0.2 wt. %, in similar fashion to what has been previously reported byHelmy et al (2013a) for experiments carried out over a similar temperature range. The estimated DAs MSS/sulf is 0.6 ± 0.2(Table 3).…”

supporting

confidence: 88%

“…Since 90's, several experimental studies have demonstrated the existence of liquid immiscibility between arsenide and sulfide melts at magmatic temperatures (850-1200 ºC) (Makovicky et al 1990(Makovicky et al , 1992Fleet et al 1993;Tomkins 2010;Helmy et al 2010Helmy et al , 2013aSinyakova and Kosyakov 2012). These studies have further showed that arsenide melts are efficient collectors of platinum-group elements (PGE, Os, Ir, Ru, Rh, Pt and Pd) because these metals are strongly concentrated into arsenides once arsenide This is the peer-reviewed, final accepted version for American Mineralogist, published by the Mineralogical Society of America.…”

Section: Introductionmentioning

confidence: 99%

“…Copper and Fe are incompatible in the arsenide melt: DCu arsenide melt/sulfide melt around 0.55, and DFe arsenide melt/sulfide melt = 0.30 ± 0.02. The distribution of these base metals between arsenide and sulfide melts is consistent with previous studies.For example,Helmy et al (2013a) found that the affinities of base metals for immiscible arsenide melt follow the order Ni >> Fe = Cu. In their experiments, which focused on studying phase relations in the As-bearing Fe-Ni-Cu system, Helmy et alThis is the peer-reviewed, final accepted version for American Mineralogist, published by the Mineralogical Society of America.The published version is subject to change.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Partition behavior of platinum-group elements during the segregation of arsenide melts from sulfide magma

Piña

Gervilla

Helmy

et al. 2020

American Mineralogist

View full text Add to dashboard Cite

show abstract

supporting

confidence: 88%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Partition behavior of platinum-group elements during the segregation of arsenide melts from sulfide magma

Piña

Gervilla

Helmy

et al. 2020

American Mineralogist

View full text Add to dashboard Cite

show abstract

“…In As‐rich sulfide melting experiments, Pt and Ir form nanoclusters with As in sulfide melts even when undersaturated in HSEs (Helmy et al. 2013), which could provide a transport mechanism for the preferential extraction of Ir and Pt relative to Os and Ru. This mechanism may also facilitate the nucleation of discrete PGE phases in impact‐melted R chondrite sulfides that cooled in situ.…”

Section: Discussionmentioning

confidence: 99%

Sulfide‐dominated partial melting pathways in brachinites

Crossley

Ash

Sunshine

et al. 2020

Meteorit & Planetary Scien

View full text Add to dashboard Cite

The brachinite family, which includes brachinites and ungrouped achondrites with compositional and isotopic similarities to brachinites, comprises FeO-rich, olivine-dominated achondrites whose compositional and mineralogic variability is correlated with oxidation state. Most classical brachinites are derived from precursors that were more oxidized and sulfur-rich than those of ungrouped "brachinite-like" achondrites. This is manifest in the distinct Fe-Ni-S systems among brachinite family precursors, which were sulfide-dominated for the most oxidized brachinites and metal-dominated for the least oxidized brachinite-like achondrites. Consequently, highly siderophile element behavior was controlled through melting and removal of their dominant host phase in the precursor, which was likely pentlandite in sulfide-dominated systems and kamacite/taenite in metal-dominated systems. Anomalous Ir/Os and Pt/Os ratios of oxidized brachinites may be attributed to selective complexing during melting of As-rich pentlandite, consistent with our observations of impact-melted sulfides in R chondrite NWA 11304, although further experimental work is needed to model this process. The apparent redox trend among the brachinite family is consistent with silicate FeO content and Fe/Mn ratios, which may be used as a proxy for determining the relative oxidation state of brachinite family members. Based on our analyses, we make several recommendations for reclassification of samples into a continuum of oxidized to reduced endmembers for the brachinite family. Along with a common range of Δ 17 O, this evidence is consistent with either formation on a common heterogeneous parent body, or at least from the same nebular reservoir, with variable O and S fugacities, resulting in mineralogically distinct igneous products for oxidized and reduced endmembers. Sulfur-bearing, oxidized differentiation may extend to other bodies that formed at or beyond the snow line in the early solar system, and should be considered when interpreting observational data for asteroids in upcoming missions.

show abstract

“…1993;Wood 2003;Helmy et al 2013). Helmy et al (2013) conclude that Pt and Pd associate with As nin preference to S 2before saturation of arsenide in sulphide melts (perhaps as nano-metre sized As-metal clusters). The latter authors propose that the affinities of the precious and basemetals for an immiscible arsenide melt are: Pt>Pd>Ni>>Fe≈Cu.…”

Section: Arsenide As a Collector Of Pge At Cliffmentioning

confidence: 99%

Platinum-group element remobilization and concentration in the Cliff chromitites of the Shetland Ophiolite Complex, Scotland

et al. 2018

View full text Add to dashboard Cite

The ~492 Ma Shetland Ophiolite Complex contains an extensive mantle section, within which numerous podiform chromitite bodies formed during melt percolation in a supra-subduction zone setting. One of the Shetland ophiolite chromitite localities has an unusual style of platinum-group element (PGE) mineralization. Specifically, the Cliff chromitite suite has relatively high (>250 ppm) Pt plus Pd, compared to other chromitites in the Shetland Ophiolite Complex. In this study, we apply petrographic observation, mineral chemistry and novel X-ray microtomography data to elucidate the petrogenesis of PGE-bearing phases at Cliff. The combined datasets reveal that the PGE at Cliff have probably been fractionated by an As-rich fluid, concentrating Pt and Ir into visible (0.1–1 µm) platinum-group minerals (PGM) such as sperrylite and irarsite, respectively. The high (>1 ppm) bulk-rock concentrations of the other PGE (e.g. Os) in the Cliff chromitites suggests the presence of abundant fine-grained unidentified PGM in the serpentinized groundmass. The spatial association of arsenide phases and PGM with alteration rims on Cr-spinel grains suggests that the high Pt and Pd abundances at Cliff result from a late-stage low-temperature (e.g. 200–300°C) hydrothermal event. This conclusion highlights the potential effects that secondary alteration processes can have on modifying and upgrading the tenor of PGE deposits.

show abstract

Fractionation of platinum, palladium, nickel, and copper in sulfide–arsenide systems at magmatic temperature

Cited by 62 publications

References 47 publications

Partition behavior of platinum-group elements during the segregation of arsenide melts from sulfide magma

Partition behavior of platinum-group elements during the segregation of arsenide melts from sulfide magma

Sulfide‐dominated partial melting pathways in brachinites

Platinum-group element remobilization and concentration in the Cliff chromitites of the Shetland Ophiolite Complex, Scotland

Contact Info

Product

Resources

About