OREAS 502d was prepared from a blend of porphyry copper-gold ores, barren granodiorite and a minor quantity of Cu-Mo concentrate. The ores were sourced from both the Cadia Mine and Northparkes Mine. Both mines are located in the central west of New South Wales, Australia. The barren granodiorite was sourced from the mafic, S-Type, Late Devonian Bulla Granodiorite complex located in northern Melbourne, Australia.
Twenty-two commercial analytical laboratories participated in the program to certify the elements shown below. The following methods were employed:
- Gold by 15-50g fire assay with AAS (17 laboratories) or ICP-OES (4 laboratories) finish;
- Gold by 10-50g aqua regia digestion with ICP-MS finish (10 laboratories) and AAS (5 laboratories) finish;
- 4-acid digestion for full elemental suite ICP-OES/MS finish (up to 19 laboratories depending on the element)
- Aqua regia digestion for full elemental suite ICP-OES/MS and AAS finish (up to 21 laboratories depending on the element).
Gold by instrumental neutron activation analysis (INAA) on 20 x 85mg subsamples was undertaken to confirm homogeneity (at ANSTO, Lucas Heights, Australia).
| CRM Code
||Principle Certified Values
||Au 0.499 ppm
||Mo 249 ppm
|| porphyry copper-gold