De Grey Mining Limited (ASX: DEG) announced that the latest extensional drilling at Falcon intrusion within the Hemi discovery in Mallina Gold Project in WA has intersected major depth extensions of its gold mineralisation with multiple new footwall lodes beginning to develop as the intrusion thickens at depth.
Significant results included 55m @ 1.0g/t Au from 263m and 16.5m @ 1.1g/t Au from 324.5m; and 24m @ 0.9g/t Au from 302m and 12.5m @ 1.30g/t Au from 331m. DEG noted that Falcon intrusion is thickening to 100m as drilling extends mineralisation at depth.
The company reported that shallow infill drilling showed strong continuity of mineralisation, with significant hits of 19m @ 1.3g/t Au from 55m within an overall interval of 42m @ 1.0g/t Au from 45m; 20m @ 1.8g/t Au from 64m; and 12m @ 1.3g/t Au from 45m.
Drilling at Falcon
The company had commenced RC and diamond drilling to 80m x 40m spacing and a maximum vertical depth of approximately 280m at Falcon intrusion. Important intercepts reported till date included 31m @ 1.5g/t Au in HERC261D; 31m @ 3.3g/t Au in HERC296; and 3m @ 2.6 g/t Au in HERC271D.
DEG said that the latest extensional drilling demonstrated thick zones of gold mineralisation within an intrusion up to 100m thick, 350m down dip and over 1,000m of strike. The company said that the mineralisation dips steeply to the east and remains open at depth along the entire strike length.
DEG announced that the recent deepest holes occurred on most 80m spaced sections and intersected significant mineralisation.
Highlights included 26.3m @ 2.3g/t Au from 309m including 5.7m @ 4.4g/t Au from 325.3m in HERC298D; 34.2m @ 1.8g/t Au from 212m including 4.0m @ 4.1g/t Au from 218.0m and 7.0m @ 3.7g/t Au from 230.0m in HERC407D; 65m @ 1.4g/t Au from 324m including 0.5m @ 17.3g/t Au from 330.0m in HERC416D; and 55m @ 1.0g/t Au from 263m including 3.5m @ 3.6g/t Au from 298.0m and 16.5m @ 1.1g/t Au from 324.5m in HERC400DW1.
Continuity of mineralisation
The company said that shallow infill drilling showed strong continuity of mineralisation, with significant hits of 19m @ 1.3g/t Au from 55m in HERC516 within an overall interval of 42m @ 1.0g/t Au from 45m; 20m @ 1.8g/t Au from 64m in HERC517; 19m @ 1.8g/t Au from 77m in HERC518; and 12m @ 1.3g/t Au from 45m in HERC511.
DEG said that the exploration has also started to define a footwall lode below the main lode. Intercepts from this area included 20.1m @ 1.0g/t Au from 324m in HERC402D; and 20.9m @ 1.9g/t Au from 369min HERC299DW1 (previously reported).
The company said that additional footwall lodes are becoming apparent in deeper drilling, as the intrusion thickens at depth.
Next phase of drilling at Falcon
DEG reported that at Falcon, the next phase of drilling includes 160m spaced step out diamond holes to test the main mineralised zone at a vertical depth of around 450m and will be extended to test the new footwall lodes. The company said that this work has the potential to further significantly expand the gold endowment at Falcon.
It may be noted that the Falcon intrusion extends for at least another 2km to the south. Drilling across this area to date has not defined significant mineralisation. However, the bulk of this work is wide-spaced, shallow aircore drilling, and further drilling to effectively test this zone in more detail is required.
DEG said that follow up aircore drilling will be undertaken to test for strike extensions to mineralisation. The company reported that the programs of follow up RC and diamond drilling aimed at extending resources at depth and laterally are underway.
De Grey General Manager Exploration Phil Tornatora said: “The latest extensional drilling at Falcon demonstrates the increasing scale of the zone with mineralisation now intersected over 1km strike and over 350m in depth. New 160m spaced step out diamond drilling is underway to extend mineralisation to approximately 450m depth.
The intrusion is increasing to approximately 100m thick at depth and multiple new footwall lodes are beginning to develop. Infill drilling is also providing confidence in the continuity and consistency of gold mineralisation.
Falcon is open at depth and deeper step out diamond drilling is being prioritised to test this potential. These recent results, and further depth extensions, have the potential to significantly increase the already substantive gold endowment at Falcon.”
*Image Source: De Grey Mining Limited