OREAS 683b

OREAS 683b is a copper–nickel–platinum group element (PGE) certified reference material (CRM) prepared from a blend of PGE-rich ore, nickel sulphide ores, copper concentrates, and barren gabbronorite. The principal PGE component was sourced from the Dishaba Mine (Limpopo Province, South Africa), a well-known operation on the western limb of the Bushveld Igneous Complex characterised by Merensky and UG2 reef mineralisation hosting platinum, palladium, rhodium and gold in sulphide and alloy phases.

Nickel contributions were derived from high-grade Ni sulphide ores from the BHP Leinster and Xstrata Cosmos deposits, both hosted within komatiitic ultramafic sequences of the Agnew–Wiluna greenstone belt (Western Australia). Copper was introduced using DeGrussa and Cobar high-grade Cu concentrates from Western Australia and New South Wales, respectively. Additional gold material was incorporated via PGE-bearing Frogs Leg ore (Western Australia).

The matrix was adjusted using barren gabbronorite sourced from the Black Hill Norite Complex (near Adelaide, South Australia), providing an ultramafic–mafic host consistent with the geological environment of Ni–Cu–PGE sulphide mineralisation.

OREAS 683b has been characterized using the following methods:

• Full ICP-OES and ICP-MS elemental suites by 4-acid (HNO3-HF-HClO4-HCl) digestion
• Sodium peroxide fusion or lithium borate fusion with full ICP-OES and ICP-MS suites
• Au, Pt and Pd by lead collection fire assay with ICP-OES and ICP-MS
• Au, Pt, Pd, Ir, Rh and Ru by nickel sulphide (NiS) collection fire assay with ICP-OES and ICP-MS

Certified values for applicable analytes are operationally defined for each method, with results under OREAS ISO 17034 scope of accreditation.