De Grey Mining Limited (ASX: DEG) has announced the intersection of exceptional high-grade gold including 19m at 42 grams per tonne from 170m from the drilling at the Crow Zone at the Hemi Gold Discovery in Western Australia.
The company reported thick, high-grade gold intercepts with visible gold at Crow. Highlights include 64m @ 13.4g/t Au from 141m, including 19m @ 42.0g/t Au from 170m (which in turn includes 8m @ 84.7g/t).
Additional significant RC results at Crow include 12m @ 2.4g/t Au from 109m; 24m @ 1.1g/t Au from 51m; and 31m @ 2.2g/t Au from 69m.
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.
Three zones in Hemi
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. Crow is a northeast-trending gold in bedrock anomaly and is located immediately adjacent and north of the Aquila zone.
The overall scale of Hemi continues to increase with dimensions growing to approximately 2.5km north to south and 2km west to east with three main zones (Aquila, Brolga, and Crow) defined within this large gold system.
Drilling at Hemi
The Company had recently commenced aircore (AC), reverse circulation (RC) and diamond drilling (DD) at Hemi to test and extend the known mineralisation.
Initial aircore drilling at Crow defined a large system +1km long and +400m wide. A program of RC and diamond drilling was then undertaken to define and extend mineralisation.
DEG said that it has one aircore rig operating south of Aquila and one operating in the Greater Hemi region looking for mineralised extensions and Hemi look-alikes. The company said that two RC rigs are following up extensions identified in aircore drilling and two diamond rigs are drilling depth extensions.
Drilling at Crow zone
The company said that at Crow, RC and diamond drilling targeted new mineralisation to the north of Aquila and throughout the large Crow intrusion.
DEG noted that the style of mineralisation is similar to the Aquila and Brolga zones with more discrete lodes of sulphide rich altered and brecciated intrusion. The company said that the recent drilling shows the lodes can host high grade intervals within broader zones of lower grade mineralisation.
De Grey announced that the latest drill results have provided extensions and infill to the Crow zone. The company also reported new high-grade gold intercept in HERC238 at Crow zone.
High-grade gold intercepts from Crow
DEG reported significant high-grade gold hits from the Crow zone.
De Grey said that the drill hole HERC238 is an example of very high-grade gold mineralisation with visible gold. The company said that at HERC238, the high-grade intercept of 64m @ 13.4g/t also includes an interval of 19m @ 42g/t. This interval includes a continuous run of individual 1m assays of 43.4, 229.0, 55.2, 42.0, 106.0, 103.0, 46.3, and 53.1g/t from an overall interval of 8m @ 84.7g/t.
Other important hits include 37m @ 22.3g/t Au from 155m in HERC238 (incl 19m @ 42g/t Au from 170m) and 8m @ 3.1g/t Au from 197m; 12m @ 2.4g/t Au from 109m in HERC175; 12m @ 2.2g/t Au from 72m in HERC220; 4m @ 2.5g/t Au from 116m in HERC221; 10m @ 1.1g/t Au from 149m in HERC221; 24m @ 1.1g/t Au from 51m in HERC225; 35m @ 0.8g/t Au from 84m in HERC226; 7m @ 1.7g/t Au from 42m in HERC227; and 31m @ 2.2g/t Au from 69m in HERC227.
De Grey reported that the new results indicate Crow hosts a number of stacked subvertical to moderately south dipping lodes with many remaining open at depth and along strike. The company said that further drilling is continuing to extend and infill mineralisation.
Latest updates and next steps
De Grey announced that follow-up aircore drilling will be undertaken to test for strike extensions to mineralisation. The company said that programs of follow up RC and diamond drilling aimed at extending resources at depth and laterally are underway.
Management comments
De Grey Managing Director Glenn Jardine said: “Extensional and definition RC and diamond drilling at Crow on an 80 metre pattern commenced only recently in July. The exceptional result in HERC238 is the best result at the Mallina Project to date and has transformed our perceptions of the large Crow intrusion. It follows recent announcements of the discovery of new sub-vertical lodes in Crow, together with mineralised extensions of Crow to the north-west.
The significance of the new RC results at Crow goes beyond the results in HERC238. They demonstrate the potential for Crow to significantly add to the overall gold endowment at Hemi and to meaningfully contribute to a potential large scale, near surface open pit production scenario. The mineralised footprint at Crow is currently approximately 1,000m by 400m and remains open.
The Company’s drilling program is working successfully toward our strategic goal of making Hemi a Tier 1 scale gold deposit and demonstrating the potential for further upside on a tenement wide scale.”