OREAS 241 was prepared from a blend of gold ore and barren greenstone. The ore was sourced from the Frogs Leg Gold Mine located 19km west of Kalgoorlie in Western Australia. The Cambrian greenstone was sourced from a quarry 145km north of Melbourne, Australia.
Thirty-one commercial analytical laboratories participated in the program to certify the elements reported below.
- Gold by fire assay (25-50g charge weight) with AAS and ICP-OES finish;
- Gold by aqua regia digestion (15-50g sample weight) with ICP-OES and/or ICP-MS finish;
- Gold by cyanide leach (20-200g) with AAS or ICP-MS finish;
- Gold by x-ray photon assay on ~350g sample weights;
- Full ICP-OES and ICP-MS elemental suites by 4-acid digestion;
- Full ICP-OES and ICP-MS elemental suites by aqua regia digestion.
To confirm homogeneity, gold by instrumental neutron activation analysis (INAA) was undertaken on 20 x 85mg subsamples (see Table 5 in the ‘Homogeneity Evaluation’ of the Certificate).
| |
Analyte
|
Certified Value
|
1SD
|
CRM State
|
Matrix
|
Mineralisation
|
| |
Au by fire assay
|
6.91 g/t
|
0.309
|
primary
|
greenstone
|
orogenic lode gold
|