OREAS 992b is a copper sulphide certified reference material (CRM) prepared from a nickel matte by-product during the refining process at a nickel refinery. Fifteen ‘umpire’ laboratories undertook copper, gold, silver and moisture analysis on the sample as received but results are corrected to dry basis. The term ‘umpire’ here refers to the routine analysis by these laboratories using classical methodologies for precious and base metals. Fifteen geoanalytical laboratories also participated in the analytical program to undertake the following:
- Full elemental suites by peroxide fusion with ICP-OES and MS finish;
- Full elemental suites by 4-acid digestion with ICP-OES and MS finish;
- Total S by IR combustion furnace;
- Gold by instrumental neutron activation analysis (INAA) to confirm homogeneity (undertaken by ANSTO, Lucas Heights).
| CRM Code |
Principle Certified Values |
State |
Matrix |
Mineralization |
| OREAS 992b |
Cu 45.98% |
Au 15 ppm |
Ag 344 ppm |
primary |
concentrate |
komatiite-hosted nickel sulphide |