De Grey Mining Limited (ASX: DEG) has announced strike extensions and visible gold including 31m @ 3.3g/t Au from 101m from the drilling at its Hemi Gold Discovery, located approximately 60km south of Port Hedland in Western Australia.
The company reported that broad mineralised zone was extended from 800m to more than 1,000m along strike and 300m below surface at Falcon.
Notable results included 31m @ 3.3g/t Au from 101m that is 50m downdip of previous intersection of 50m @ 3.3g/t Au from 50m. DEG said that the mineralisation remains open across strike and down dip.
Drilling also intersected 42m of sulphide altered intrusion containing visible gold. The company said that this extends mineralisation 50m – 100m below previous intersection of 25m @ 2.2g/t Au from 124m.
Other intersections along the well mineralised zone included 74m @ 0.9g/t Au from 88m and 31m @ 1.3g/t Au from 209m; and 32m @ 2.4g/t Au from 43m and 8m @ 5.5g/t Au from 99m.
The company said that Falcon remains open along strike, down dip and at depth with extensional RC and diamond drilling continuing.
Mallina gold project
De Grey’s Mallina Gold Project is located approx. 60km south of Port Hedland in the Mallina Province of Western Australia.
The project hosts numerous large deposits, of which significant gold deposits include Withnell, Mallina, and Toweranna. Other prospects include Hemi, Antwerp, and Scooby. Hemi is surrounded by world-class infrastructure within a Tier 1 mining jurisdiction.
Hemi is a discovery under 30m of transported cover, with two zones of strong, broad sulphide rich alteration with high-grade gold mineralisation partially defined in the Aquila and Brolga zones. De Grey had recently defined a third gold in bedrock zone called the Crow zone located immediately adjacent and north of the Aquila zone.
DEG’s drilling west of Brolga and south of Aquila delineated a highly brecciated and extensively sulphide altered subvertical intrusion. This new intrusion named Falcon is located approximately 600m west of Brolga, and immediately south of the Aquila deposit.
Drilling at Hemi
The company had commenced step out RC and diamond drilling at the Hemi discovery. DEG reported that the ongoing drilling has extended mineralisation along strike and at depth at Hemi.
High-grade results
De Grey announced significant new gold results from the drilling at the Falcon.
DEG said that the RC drilling up-dip of previous drill diamond hole HERC253D on section 7691960N intersected 32m @ 2.4g/t Au from 43m and 8m @ 5.5g/t Au from 99m in HERC412. The company said that the mineralisation remains open up-dip of drill hole HERC256 on section 7691560N.
42m of sulphide altered intrusion
De Grey said that a diamond tail on hole HERC402D on section 7691560N intersected highly brecciated and sulphide altered intrusion from 198-240m with the hole finishing at 400m. DEG said that 42m of sulphide altered intrusion containing visible gold was intersected in HERC402D.
The company reported that visible gold was noted at 210m. DEG said that this hole is targeting mineralisation at depth below the previously reported intersection of 25m @ 2.2g/t Au from 124m in HERC256. De Grey said that assays remain pending for this diamond core hole, in addition to a number of RC and diamond holes drilled in the ongoing program.
The company noted that mineralisation remains open at depth on section 7691320 below HERC296 which intersected 31m @ 3.3g/t Au from 101m extending the mineralised horizon beyond the previous result of 12m @ 2.0g/t Au.
Important results
The significant new RC and diamond drilling results from Falcon include 32m @ 2.4g/t Au from 43m in HERC412 (incl 2m @ 12.8g/t Au from 60m) and 8m @ 5.5g/t Au from 99m in HERC412 (incl 2m @ 13.4g/t Au from 104m); 5.5m @ 2.6g/t Au from 281.75m in HERC254D (incl 1.1m @ 10.8g/t Au from 286.16m); 74m @ 0.9g/t Au from 88m in HERC414 and 10m @ 1.9g/t Au from 186m (incl 3m @ 3.3g/t Au from 188m) and 31m @ 1.3g/t Au from 209m (incl 2m @ 5.9g/t Au from 231m); 24.5m @ 0.6g/t Au from 102.52m in HERC245D and 9.5m @ 2.5g/t Au from 132m (incl 1m @ 9.4g/t Au from 136m) and 10m @ 2.7g/t Au from 160m; 10m @ 1.8g/t Au from 62m in HERC413; 25.4m @ 1.8g/t Au from 226.6m in HERC236D (incl 1m @ 9.3g/t Au from 234m and 3m @ 3.2g/t Au from 244m) and 12.6m @ 1.1g/t Au from 271.36m.
Other significant results include 8m @ 1.6g/t Au from 267.54m in HERC263D; 31m @ 3.3g/t Au from 101m in HERC296 (incl 7m @ 10g/t Au from 119m); 10m @ 1g/t Au from 230m in HERC406; and 11m @ 1g/t Au from 213m in HERC273.
Increase in broad mineralised zone
The company reported that the Falcon intrusion is now defined by aircore drilling over approximately 3.0km in strike. DEG said that strong mineralisation has been defined over a strike length of approximately 1km.
DEG noted that the bedrock mineralisation is covered by approximately 30m to 40m of transported material. This is similar to the Aquila, Brolga and Crow deposits.
The company said that the mineralisation is intimately associated with highly brecciated and extensively sulphide altered portions of the north-south orientated subvertical intrusion. The style and intensity of alteration and brecciation is similar to the nearby Aquila deposit.
Latest updates and next steps
DEG announced that the follow up aircore drilling will be undertaken to test for strike extensions to mineralisation.
The company said that the programs of follow up RC and diamond drilling aimed at extending resources at depth and laterally are underway. DEG said that the RC drilling is continuing on an 80m x 40m pattern, with diamond tails to test mineralisation at depth.
Management comments
De Grey Managing Director Glenn Jardine said: “Falcon was identified as a separate intrusion zone at Hemi in September. The Company has been following up the initial positive shallow aircore drill results with infill and extensional RC and diamond drilling.
The latest results demonstrate the gold endowment of this zone along a strike of 1,000m and to a depth of at least 300m. Mineralisation remains open down dip, along this strike and up dip on some sections.
Falcon has the potential to provide an important contribution to the overall gold endowment at Hemi. Extensional RC and diamond drilling will remain a focus at Falcon.
The Company has seven drill rigs operating on site; two aircore rigs, three RC rigs and two diamond rigs. A third diamond rig is being mobilised and is expected to commence by early December. As well as delineating the existing zones at Hemi, aircore and RC drilling is now progressively expanding to known and new intrusive targets in the Greater Hemi area.”