Emmerson Resources Ltd (ASX:ERM) has intersected visual gold and copper in drilling at Hermitage Prospect, part of a cluster of prospects within the northern corridor of its 100%-owned Tenant Creek tenements in the Northern Territory.
The company is hard at work on its current drilling program, with assays due next month.
The latest drill hole completed at Hermitage (HERCDD010) intersected:
- Extensive malachite in voids and vugs within hematite ironstone (from 74 metres down hole);
- Native copper both in the ironstone and as vug fill;
- Visible gold in massive hematite-magnetite-quartz that is terminated by a 10-metre wide fault/shear zone (at 171 metres);
- Chalcopyrite as veins, fractures and cement in quartz-dolomite-hematite hydrothermal breccia (below the fault) and as blebs (to 190 metres) before finally intersecting;
- Chalcopyrite and bornite in stockwork quartz veins, fractures and stringers that gradually grade to minor blebs/specks of chalcopyrite (at 222 metres down the hole).
The drill hole confirms copper mineralisation continues at depth, following previous drilling at hole HERC003 which delivered (116 metres at 3.4% copper and 0.88 g/t gold).
HERCDD010 was drilled as an angled scissor hole in the opposite direction to previous drilling to test below the fault.
“Hallmarks of significant discovery”
Hermitage continues to deliver strong results for Emmerson.
“Hermitage is shaping up as one of our most exciting projects and continues to exhibit hallmarks of a significant gold-copper discovery," Emmerson’s managing director Rob Bills said.
"New zones of mineralisation continue to be intersected with this latest drill hole intersecting visible gold, plus a new zone copper mineralisation below the fault that truncated the previous high-grade gold and copper in discovery drill hole HERCDD003.
“This new zone of copper mineralisation consists of bornite-chalcopyrite hosted by breccias and stockwork quartz veins – interpreted to be the feeder conduit to the overlying hematite-magnetite ironstones.
"The mineralisation is hosted in multiple, east-west striking structurally controlled, ironstone bodies that are steeply north plunging and now with this intersection, are also open down plunge.
"Whilst the tabular to pipelike geometry of the mineralisation constrains the surface (horizontal) footprint as is typical in most of the Tennant Creek iron-oxide copper-gold deposits, the grade and plunge extent are the main determinants of the future potential.
“Furthermore, there are now three distinct targets at Hermitage that include: shallow copper in the oxide zone; gold associated with massive hematite and, primary copper mineralisation below the fault hosted in breccias, stockwork veins and fractures.
“This has important exploration implications both at Hermitage in terms of further potential but also in the region where the stockwork and fracture-controlled chalcopyrite-bornite mineralisation represents a new target.”
Phase 2 delivers visual gold and copper
The Hermitage, North Star, Jasper Hills, Katherine Star and Northern Star prospects are in mining lease (ML) 30177 and the Edna Beryl, Thrace and Macedon prospects are in ML 705. The prospects occur along the northern gravity corridor, within denser, hematitic shales, jasper and ironstones which are the typical host to the high-grade mineralisation.
Importantly for Emmerson, there has been little modern exploration. While some areas have restricted access, Emmerson hopes to unlock these in the future.
In the meantime, it has been following through on its Phase 1 and Phase 2 programs, with RC drill hole HERC003 intersecting 116 metres at 3.4% copper and 0.88 g/t gold and follow-up Phase 2 diamond drilling extending this discovery hole a further 0.5 metres, intersecting massive hematite magnetite ironstone with blebs of chalcopyrite (up to 2% of volume) before encountering broken ground likely associated with a late fault.
This hole was eventually abandoned due to drilling difficulties.
Drill hole HERCDD005 (Phase 2 program) intersected a previously unknown ironstone that contains a 38-metre interval of mineralisation consisting of malachite, native copper and chalcopyrite ± bornite.
Read: Emmerson Resources hits visible copper during follow-up drilling at Hermitage in Tennant Creek
This mineralisation occurs 38 metres down the drill hole and has been dispatched for assay with expected results in July 2022.
The most recent diamond drill hole HERCDD010 was an angled (-73 degree) scissor hole designed to test beneath the post mineral fault encountered in HERC003 and HERCDD005.
Significantly, it has revealed that the upper copper zone grades to disseminated gold (with visible gold, Photo 3) hosted in massive and brecciated hematite-magnetite-quartz before encountering the fault/shear zone from 171 to 180 metres (down the drill hole).
Free disseminated gold in hematite-magnetite-quartz ironstone (from 164.7 metres).
Beneath the fault, this is followed by an 11-metre wide zone of quartz-dolomite-hematite hydrothermal breccia that hosts chalcopyrite as both blebs and matrix fill (up to 2% volume).
All visual volume percentage estimates are approximate only and accurate values will be reported once assay results are returned from the laboratory. First assay results from Hermitage are expected in July 2022.
Other drill holes now completed in phase 2 drilling include:
- HERCDD006 which intersected hematite-jasper-quartz ironstone from 127 to 184 metres (downhole) with visible malachite and native copper in the oxide zone and chalcopyrite blebs/stringers at depth;
- HERC008 intersected ironstone from 53 to 103 metres (down the hole) with visible malachite grading to chalcopyrite;
- HERC009 intersected the main ironstone at 96 metres and traversed vuggy hematite and jasper-hematite with malachite blebs until the hole was terminated due to drilling difficulties at 137 metres;
- HERC011 intersected the main ironstone from 70 to 131 metres (down the hole) with malachite blebs from 70-75 metres; and
- HERC012 intersected the main ironstone from 88 to 137 metres with visible disseminated blebs of malachite and chalcopyrite indicating the mineralisation and ironstone is still open to the east.