Platinum-group mineralization in the Rum layered intrusion, Scottish Hebrides, UK

Abundant and diverse platinum-group minerals occur in the Rum layered intrusion, Inner Hebrides, Scotland, Platinum-group minerals are associated with chromite-rich horizons in both the Eastern and Western layered series, and are enclosed by Ni- and Cu-rich sulphides, or silicates. The most common phases are Pd-Cu alloys; Pt-Fe alloys; laurite (Ru(Ir,Os)S-2); sperrylite (PtAs2); and Pt-Pd-bearing bismuthides, tellurides and antimonides, The mineralization on Rum is due to: (1) initial concentration in the parental magma linked to a high degree of melting associated with mantle plume activity, and (2) localized concentration due to magma mixing and subsequent crystallization within an open-system magma chamber.