New high-grade gold hits strengthen underground potential at De Grey’s Mallina gold project
Special Report: There literally is no end to the high-grade gold that De Grey Mining is finding across the Mallina gold project , with the company now proving its Withnell deposit also has substantial scale and grade.
De Grey’s recent drilling and sampling has returned multiple high grades, including a half-metre hit of up to 56.9 grams per tonne (g/t) gold from 341.75m, within a broader intercept of 5.1m at 9.9g/t from 338.9m.
Other notable shallow intercepts returned were 3m at 17.1g/t from 91m, including 1m at 43.6g/t from 92m.
This shallow high-grade gold was intersected at the western end of the deposit, which De Grey says provides added scope to extend the westernmost plunging shoot laterally and at depth.
These new drilling results have extended the Withnell Lode 1 another 100m below the current resource, down to 350m, along the entire 1.2km strike length.
Importantly, within this 1.2km strike length, Lode 1 appears to be developing into three west plunging higher grade shoots, technical director Andy Beckwith said.
Lode 1 is the dominant lode within the Withnell deposit and there are also several sub-parallel lodes that have been partially drill tested.
Results from these lodes so far have returned hits of 7m at 2.2g/t from 85m in Lode 2 and 0.67m at 16.1g/t from 476.6m in Lode 12.
De Grey is still waiting on further drilling results from Lode 1 and the parallel lodes.
The overall open pit and underground resource now averages around 1200 ounces of gold per vertical metre down to about 250m below surface.
And this large gold system remains open along strike and at depth, which means De Grey hasn’t yet found the edges.
“Scale and grade are the two most important aspects of the Withnell deposit,” Beckwith noted.
“Withnell is a large 1.2km long and highly mineralised gold system that remains open both along strike and at depth.
“The average grade of the underground resource is 4.1g/t which compares favourably to existing Western Australian operating underground mines.”
Withnell is the largest gold resource within the Mallina gold project and currently hosts a combined open pit and underground resource of 4.65 million tonnes at 2.9g/t for 429,300oz of gold.
De Grey has also confirmed that its pre-feasibility studies will be evaluating the potential to mine the Withnell underground resource on the basis of a conceptual and conventional longhole open stoping mining method accessed by a decline off the proposed open pit cutback.
De Grey’s ongoing exploration focus of finding additional resources at depth is considered likely to improve the evaluation and provide potential to extend the overall mine life.
The company is also continuing resource extension drilling at both the Withnell and Mallina deposits.