Alba Mineral Resources plc said it had received notable results from its first assay on bulk sample concentrates produced at its pilot processing plant at Clogau-St David’s gold mine, North Wales.
The underground bulk samples were collected during October 2020 with the first bulk sample taken from previously worked areas of the mine.
The junior miner said it had not been anticipating high-grade results from the initial processing exercise but was very pleased to report some “very notable grades”.
Results from an independent laboratory showed concentrates from the Jack Williams lode and floor material from Tyn-Y-Cornel area returned grades of 20.4 to 165.5 g/t.
Concentrates produced from two other bulk sample locations returned lower grade results, but Alba said it expected grade variability due to the locations of the bulk sample and the Clogau vein system’s inherent nature of irregular gold dissemination.
| Sample ID | Location | Concentrate sample mass (g) | Concentrate Au (g/t) |
| JW-2-C | JW | 158 | 53.5 |
| JW-3-SM | JW | 158 | 81.5 |
| JW-5-SM | JW | 157 | 22.9 |
| JW-6-C | JW | 156 | 31.3 |
| JW-6-SM | JW | 162 | 50.6 |
| JW001-7-C | JW001 | 151 | 20.4 |
| JW003-16-C | JW003 | 157 | 52.3 |
| JWSP-19-C | JW-SP | 161 | 48.6 |
| JWSP-20-C | JW-SP | 151 | 45.8 |
| 2019-1-C1 | 2019 | 164 | 33.3 |
| 2019-15-C | 2019 | 163 | 165.5 |
broken stock floor material in the mined-out areas at Tyn-y-Cornel (Alba Mineral Resources)
Further bulk samples due to be taken this year will be from new unworked veins, which have prospects for higher-grade mineralisation.
The company added that the value of tailings returned negligible gold grades which indicated that the plant was operating with high efficiency.
STRATEGY
The irregular distribution and grade of gold is due to the high nuggety-effect of the Clogau vein system.
This has formed the basis of the miner’s exploration strategy of a combination of drilling to identify gold-bearing structures, and bulk sampling to obtain a representative idea of gold grade.
The company has yet to combine these strategies in a particular zone, because all the bulk sampling last year was carried out in previously mined areas, not areas identified through Alba’s own drilling.
Alba expects this will change to taking bulk samples from new and unworked veins identified through the company’s own drilling, and where the prospects for higher-grade mineralisation are expected to be greater.