| Reference Type | Journal (article/letter/editorial) |
|---|
| Title | Coupled substitutions in PGE-enriched cobaltite: new evidence from the Rio Jacaré layered complex, Bahia state, Brazil |
|---|
| Journal | Mineralogical Magazine |
|---|
| Authors | Barkov, Andrei Y. | Author |
|---|
| Fedortchouk, Yana | Author |
| Campbell, Robert A. | Author |
| Halkoaho, Tapio A.A. | Author |
| Year | 2015 (October) | Volume | 79 |
|---|
| Issue | 5 |
|---|
| Publisher | Mineralogical Society |
|---|
| DOI | doi:10.1180/minmag.2015.079.5.12Search in ResearchGate |
|---|
| Generate Citation Formats |
|---|
| Mindat Ref. ID | 244693 | Long-form Identifier | mindat:1:5:244693:0 |
|---|
|
| GUID | 0 |
|---|
| Full Reference | Barkov, Andrei Y., Fedortchouk, Yana, Campbell, Robert A., Halkoaho, Tapio A.A. (2015) Coupled substitutions in PGE-enriched cobaltite: new evidence from the Rio Jacaré layered complex, Bahia state, Brazil. Mineralogical Magazine, 79 (5) 1185-1193 doi:10.1180/minmag.2015.079.5.12 |
|---|
| Plain Text | Barkov, Andrei Y., Fedortchouk, Yana, Campbell, Robert A., Halkoaho, Tapio A.A. (2015) Coupled substitutions in PGE-enriched cobaltite: new evidence from the Rio Jacaré layered complex, Bahia state, Brazil. Mineralogical Magazine, 79 (5) 1185-1193 doi:10.1180/minmag.2015.079.5.12 |
|---|
| Abstract/Notes | AbstractMicrocrystals of platinum-group element (PGE)-bearing cobaltite occur in the Gulcari A deposit of vanadiferous titanomagnetite in the lower zone of the Rio Jacaré mafic-ultramafic layered intrusion, Brazil. Aggregates of cobaltite and sperrylite are cluster-like and developed generally along the boundary of Fe-Ti oxide grains with deuteric silicates. Our observations of cryptic zoning, compositional variability and interelement correlations are based on 37 analytical points (wavelength-dispersion spectrometry mode) of cobaltite, and indicate that Ir and Rh behave uniformly with Ni and antipathetically with Co which, in turn, correlates directly with S content. Iridium, Rh and Ni apparently substitute for Co in the As-enriched grain core, and the substitution mechanism invokes solid solution with a cattierite-type molecule: (Ni + Ir + Rh) + (AsS) = Co + (S2). The PGE-bearing cobaltite probably crystallized as a primary phase at 500 to 300°C, from microvolumes of a late fluid phase. The observed enrichment in S and decrease in the As:S ratio at the cobaltite grain margins is a reflection of the increase in sulfur fugacity (fS2) with decrease in temperature of crystallization. |
|---|
These are possibly similar items as determined by title/reference text matching only.
