De Grey Mining (ASX:DEG) announced that new drill results from the Diucon and Eagle deposits at its major Hemi prospect in WA’s Pilbara have increased the likelihood of a larger-than-expected open-pit mining operation.
The Diucon and Eagle finds are located to the west of the main Hemi deposit.
De Grey stated that the latest results "relate to some Diucon and Eagle resource infill and extensional drilling that was included in the June 2023 Mineral Resource Estimate. Additionally, extensional drilling was completed down plunge and down dip at Eagle, and along the strike at Diucon."
The Definitive Feasibility Study (DFS), scheduled for release in the current September quarter, will be based on the June 2023 MRE, released on 16 June 2023.
"The new extensional drill results in this release represent further upside to the DFS outcomes. There is potential for the extensions to be included in future open-pit and underground mining plans,” De Grey stated in an update to the ASX.
One intersection at Eagle yielded 10.6 grams of gold per tonne over 26.9 metres from a depth of 425.1 metres, while another reported 37.1 metres @ 3.4g/t gold from 431 metres.
"The Eagle mineralised intrusion has now been intersected over a strike of approximately 1,000 metres and a true thickness of about 200 metres, extending to at least 600 metres depth. Mineralisation remains open at depth and down plunge," De Grey explained.
"A drill program targeting mainly shallow, open-pittable resources is ongoing along the Diucon Thrust to the west of the Diucon MRE and between the Diucon and Eagle proposed pits. If successful, resources in this area may allow expansion and deepening of the proposed Diucon and Eagle pits.
"Drilling has returned some very encouraging intercepts from lodes adjacent to the Diucon Thrust (which has a strong control on mineralisation in the Hemi area), and extending up to 800 metres west of the Diucon MRE (Mineral Resource Estimate).
De Grey's General Manager of Exploration, Phil Tornatora, stated in Tuesday's release:
“Following the completion of resource definition drilling to support the DFS, the focus has shifted to exploration drilling. This is already paying dividends, with significant extensions to mineralisation at depth at Eagle and along the strike at Diucon.
"In addition to potential resource increases, deeper drilling at Hemi will support early conceptual studies into potential underground mining in the future.
"The shallower Diucon extensions have the potential to result in an expansion of the Diucon-Eagle open-pit shell outline. RC drilling is also currently taking place on the Antwerp trend, aiming to define an initial resource.”
