De Grey Mining Ltd (ASX:DEG) has received results from metallurgical test work on samples from its Toweranna open pit resource within the Pilbara Gold Project in Western Australia.
The test work assessed conventional carbon-in-leach (CIL) gold recovery from both oxidised and fresh rock at grind sizes of 150µm to 75µm.
High gold recovery was obtained from all of the oxide zone samples, ranging from 92.0% to 94.7% on varying grind sizes.
Furthermore, the fresh rock samples returned strong results with 94.7% to 96.3% gold recovery.
READ: De Grey Mining continues to intersect high-grade gold at Toweranna
De Grey’s technical director Andy Beckwith said: “Toweranna continues to grow in stature with strong resource growth potential and high recovery with conventional CIL processing characteristics.
“On-going drilling results continue to define multiple stacked lodes to at least 200m depth. Once drill assays are finalised, we will update the 0-200-metre open pit resource and run open pit optimisations.
“We are increasingly seeing free gold in the veins in core and the high gold recovery together with the simple free milling nature is encouraging.
“Toweranna is poised as a game changer as it has the potential to rapidly increase resources and improve the PFS economics.”
Toweranna is a potential open-pit and underground gold mine
Toweranna is considered one of four high priority targets alongside Withnell Underground, Mallina and Mt Berghaus, for significant resource extensions that are likely to positively impact the 2.0 million tonnes per annum PFS currently underway.
Toweranna has the potential for significant resource growth, and potential for both open pit and underground mining.
Work programs have been accelerated to expand resources to a nominal 200 metre depth and test mineralisation down to a depth of at least 600 metres.
Scout diamond drilling evaluating gold potential between 200 and 600 metres is in progress with initial assays pending.
In March 2019, a Toweranna Exploration Target was defined down to 400 metres depth in the range of 9.6-11.2 million tonnes grading 2.1-2.3 g/t gold for 680,000-800,000 ounces of gold.