De Grey strikes more high-grade gold, expands footprint at Hemi

De Grey Mining Limited (ASX: DEG) has announced further thick, high grade RC gold hits from the Aquila zone at its Hemi discovery in Western Australia’s Pilbara region, highlighting the scale of Hemi.

The company announced that near surface, broad high grades were intersected at Aquila.

Highlights include 29m @ 3.8g/t Au from 64m; 53m @ 5.9g/t Au from 117m inc. 28m @ 10.2g/t Au from 117m; and 35m @ 3.1 g/t Au from 175m inc. 16m @ 5.6g/t Au from 180m from section 29,960E, 40m west of the discovery section; and 44m @ 2.5g/t Au from 60m from section 30,080E.

DEG reported that Aquila Zone has been extended 400m west and is open along strike and at depth. De Grey said that Aquila style gold mineralisation was identified 400 metres west of Aquila with near surface gold in aircore drilling. Significant results include 33m @ 1.5g/t Au from 64m; and 20m @ 0.9g/t Au from 46m.

De Grey reported that follow up drilling to further test depth and lateral extensions at Aquila has commenced, with six drill rigs now operating on site.

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 1.7 Moz Mallina project hosts numerous large deposits. Significant gold deposits include Withnell, Mallina, and Toweranna. Other prospects include Hemi, Antwerp, and Scooby prospect.

Hemi discovery

Hemi is a new 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.

Aquila is a 1.2km long linear mineralised zone located between the Brolga and Crow intrusions and remains open in all directions.

Drilling at Aquila zone

The company had recently commenced drilling at Aquila zone at the Hemi Gold Discovery, located approximately 60km south of Port Hedland in Western Australia.

Aquila is well defined over a strike length of 800m and a depth of approximately 150m with RC and diamond drilling.  

Potential strike extension

The company reported that two high grade (+5g/t) plunging shoots appear to be developing in drilling at the Aquila zone. DEG announced that the recent aircore drilling has provided a potential 400m strike extension, and said that possible extensions to the east remain untested.

De Grey said that these high-grade shoots and lateral extension have the potential to significantly increase the open pit mining potential at Aquila.

DEG said that drilling is now targeting a vertical extension to a nominal depth of 300m along the entire strike. The company said that two high grade shoots appear to be developing at the western and eastern ends of the deposits and remain open at depth and along strike.

RC and diamond drilling

The company said that the recent RC and diamond drilling continue to extend broad scale gold mineralisation with the 4 rigs operating at all mineralized zones at Hemi. It may be noted that the RC drilling was adversely affected for a week in mid-June due to mechanical availability.

DEG reported that the RC rig has also been completing pre-collars for deeper diamond drilling at Aquila. De Grey announced that a program of step out diamond drilling on 80m sections is underway with 8 precollars already completed to extend mineralisation.

Further high-grade results

De Grey reported that recent results have defined broad, near surface, high grade mineralisation on Section 29,960 and 30,080E that remains open at depth.

Section 29,960E

Significant intercepts from section 29,960E include 29m @ 3.8g/t Au from 64m in HERC098; 53m @ 5.9 g/t Au from 117m in HERC099 including 28m @ 10.2g/t Au from 117m; and 35m @ 3.1 g/t Au from 175m in HERC101 including 16.0m @ 5.6 g/t Au from 180m.

Section 30,080E

Highlights from section 30,080E include 44m @ 2.5g/t Au from 60m in HERC092. It may be noted that two holes, HERC094D and 105D, were extended at depth by diamond drilling on section 30,080; and assays are pending for both.

AC drilling

The company announced that aircore drilling has intersected Aquila style mineralisation on section 29520E, approximately 400m to the west of Aquila.

Significant aircore results include 29,520E 33m @ 1.5g/t Au from 64m in BWAC567 (ending in mineralisation); and 30m @ 0.9g/t Au from 46m in BWAC568.

Updates and next steps

DEG announced that a detailed aeromagnetic over the Scooby to Antwerp trend has recently been completed and the results are being analysed to identify potential new intrusive targets.

De Grey reported that the aircore drilling is continuing to the southwest of Hemi targeting mineralised extensions. 

The company said that the follow up aircore drilling will be undertaken to test for strike extensions to mineralisation. De Grey said that additional RC and aircore rigs are expected to arrive on site this week.

DEG said that the extra rigs will increase drilling to 6 rigs operating in the Hemi environs and allow a ramp up of testing along strike into Scooby and Antwerp in parallel to the extensional drilling at all mineralized zones at Hemi.

De Grey said that a second aircore rig will extend coverage to the east of Hemi toward Scooby commencing this week.

DEG said that the programs of follow up RC and diamond drilling aimed at extending resources at depth and laterally are underway.

Management comments

De Grey Exploration Manager Phil Tornatora said: “The Aquila style gold mineralisation identified in highly altered intrusion 400m to the west is an exciting and significant development as it opens up the overall strike potential of the deposit.

The broad high grade mineralisation announced today is particularly encouraging demonstrating the potential to rapidly add to Aquila’s gold endowment.

We are now targeting diamond drilling to extend Aquila to at least 300m below surface along the entire strike of the deposit. The potential to extend Aquila a further 400m to the west under an interpreted shallow veneer of sediments is an exciting development and will also be targeted.

Similar potential remains to be tested to the east under the sediment contact.

Diamond core assays of the depth extensions below the recent high-grade intercepts are in the lab with results expected shortly. Stepout extension diamond drilling is on-going with a further 8 pre-collars already completed.

A second RC rig arriving next week will help accelerate drilling on all mineralised zones at Hemi.”

Written By Jonathan Norris
Jonathan is a founder of and has been covering the resources industry since 2018. With over 17 years experience in print, broadcast and online media, Jonathan has seen first hand the transformative effect of online niche media.