Platinum-, palladium- and gold-rich arsenide ores from the Kylm�koski Ni-Cu deposit

Distribution of platinum-group and chalcophile elements in the Aguablanca Ni–Cu sulfide deposit (SW Spain): Evidence from a LA-ICP-MS study

“…The Ag that is not present in BMS occurs as discrete phases such as argentop entlandite, identified within chalcopyrite (Pifia et al,20OS ) and commonly interpreted as an exsolution product (Le., Gervilla et al, 1998;Szentpeteri et al, 2002 ). Most Co is hosted by pentlandite (77 to 96%), with pyrrhotite only accounting for 2 to 5%.…”

Partition Coefficients of Platinum Group and Chalcophile Elements Between Arsenide and Sulfide Phases as Determined in the Beni Bousera Cr-Ni Mineralization (North Morocco)

“…Hence, some As enrichment mechanism is required before segregation of an arsenide melt can take place. Arsenic concentrations in magmatic melts can significantly increase via assimilation of As-rich country rocks (e.g., As-rich shales) by the magmas (Gervilla et al, 1998;Hanley, 2007;Hutchinson and McDonald, 2008;Dare et al, 2010;Godel et al, 2012). The contaminated magmas could then reach sufficiently high As concentrations to segregate arsenide droplets by immiscibility.…”

“…The capacity of arsenide melts to dissolve PGE still has not been tested in detail, although several studies show that arsenide and sulfarsenide minerals are excellent carriers of these noble metals. Natural cobaltite can dissolve up to 3.2 wt % Os, 5.8 wt % Ir, 3.3 wt % Ru, 31 wt % Rh, 1 wt % Pt, and 5.2 wt % Pd (Distler and Laputina, 1979;Gervilla et al, 1997Gervilla et al, , 1998, nickeline up to 8 wt % Pd and 0.11 wt % Pt (Cabri, 1992;Watkinson and Ohnenstetter, 1992), and maucherite up to 1.84 wt % Pd and 0.13 wt % Pt (Cabri, 1992;Cabri and Laflamme, 1976). Furthermore, experimental studies carried out by Gervilla et al (1994) in the Pd-Ni-As system reveal that nickeline and maucherite can host up to 5.3 wt % Pt and 8.6 wt % Pd at 450°C.…”

“…Holwell and McDonald (2010) and Helmy et al (2010) pointed out that Pt-Pdbearing bismuth or bismuthotelluride minerals located within Whole-rock mantle-normalized patterns for PGE and Au of As-rich orebodies from Beni Bousera, Ronda, Kylmäkoski, Vammala, and Talnotry. Data source for As-rich deposits: Ronda, Gervilla et al (1996); Kylmäkoski and Vammala, Gervilla et al (1998); Talnotry, Power et al (2004). Normalizing values are those of McDonough and Sun (1995). or between sulfide grains are the result of crystallization of evolved droplets of Te-Bi-enriched melts (that accommodated the bulk of Pt and Pd) exsolved from late-stage fractionated sulfide melt.…”

Densities and heat capacities of aqueous arsenious and arsenic acid solutions to 350°C and 300bar, and revised thermodynamic properties of , and iron sulfarsenide minerals

“…This is in agreement with our calculations showing close stabilities (i.e., solubilities) of FeAs 2 and FeAs above $550°C and is confirmed by experiments on Fe-S-As phase equilibria in water-free systems (e.g., Makovicky et al, 1992). At these temperatures, Fe-Co-Ni arsenide ± sulfide minerals can also form via immiscibility phenomena between Fe-As-S melts and mafic silicate rocks in the absence of aqueous fluids (e.g., Gervilla et al, 1998;Hem et al, 2001).…”