Reference material OREAS 123 is one of a suite of five uranium CRMs prepared from material sourced from trenching at Mantra Resources Nyota Prospect, Tanzania. The Nyota Prospect is a Karoo sandstone-hosted tabular deposit. Mineralisation is secondary and typically concentrated within medium to very coarse grained sandstone units interbedded with greywackes, siltstones or mudstones. The distribution of mineralisation is controlled by primary sedimentary features, consistent with fluid migrating along permeable coarse grained units, along bedding planes, up cross bedding and with preferential deposition occurring around ferruginous concretions and claystone clasts. Supergene enrichment is interpreted to have contributed to the high grade nature of the secondary mineralisation observed in the trenches.
Eighteen commercial analytical laboratories participated in the program to characterise the elements reported in Tables 1 to 6 (please see certificate). The following methods were employed:
- Lithium borate fusion with X-ray fluorescence (9 laboratories - 10 oxides/elements)
- Sodium peroxide fusion or lithium borate fusion with ICP-OES and ICP-MS (10 laboratories - 28 elements)
- Four acid digestion with ICP-OES and ICP-MS (16 laboratories - 38 elements)
- Thermogravimetry for Loss On Ignition (12 laboratories)
- Infra-red combustion furnace for carbon and sulphur (11 laboratories)
- Pressed powder pellet XRF for U (2 laboratories)
OREAS 123 is a SuperCRM®
| CRM Code |
Principle Certified Values |
State |
Matrix |
Mineralization |
| OREAS 123 |
U 853ppm |
Th 5.73ppm |
Ce 46.7ppm |
oxide |
sandstone/sediments |
sedimentary & hydrothermal |