OREAS 903 contains 93 certified values and is a medium grade transitional-oxide copper ore certified reference material. It is one of a suite of four transitional to oxide copper (-gold) CRMs prepared from samples sourced from CST's Lady Annie Mine, located 120 kms northwest of Mount Isa, Queensland, Australia. Mineralisation at Lady Annie is hosted in dolomitic, carbonaceous and argillaceous sandstones and siltstones. The primary copper sulphide mineralisation at depth is dominated by chalcocite and chalcopyrite and appears to be structurally controlled, being commonly associated with fault-related silicification.
Nineteen commercial analytical laboratories participated in the program. The following methods were employed:
- Four acid digestion with ICP-OES and ICP-MS finish (46 certified values)
- Aqua regia digestion with ICP-OES and ICP-MS finish (46 certified values)
- Soluble Cu via 5% H2SO4 acid leach with AAS or ICP-OES finish
- Gold via fire assay with ICP-OES, ICP-MS, AAS or solvent extraction AAS finish
OREAS 903 is a SuperCRM®
| CRM Code |
Principle Certified Values |
State |
Matrix |
Mineralization |
| OREAS 903 |
Cu 0.652% |
Cu-Sol 0.434% |
Au <5ppb |
oxide |
argillaceous sandstone |
sediment hosted |
