Other Projects in Western Australia
The Ardea WA tenure represents a large strategic land holding in one of Australia’s premier nickel sulphide and gold provinces. Ardea has several additional project mineralisation styles outside of the GNCP goethite. In addition to the other laterite hosted nickel-cobalt opportunities, Ardea’s tenure also hosts significant “greenfields” nickel sulphide and/or gold mineralisation.
Kalpini - Emu Lake nickel sulphide and gold prospect
Emu Lake is part of the Kalpini group of tenements and located 70km north-east of Kalgoorlie. The Kalpini group is home to significant lateritic nickel resources of the KNP (75Mt at 0.73% Ni and 0.04% Co, for contained metal of 476.1kt nickel and 28.8kt cobalt). There are multiple historic nickel sulphide drill hole intersections exceeding 1% nickel. Previous explorers include Jubilee Mines, Emu Nickel, Xstrata and Pioneer Nickel. The komatiite belt is known to be fertile for nickel sulphide, with previous explorers recording significant drilling results, such as 2m @ 6.2% nickel in historic core drilling (Heron Resources Limited ASX release 26 November 2013. ELD015, 2m at 6.2% Ni, 1.78% Cu, and 2.17g/t PGEs). Results of this tenor confirm unequivocal nickel sulphide endowment and prospectivity. A limited RC drilling program by Ardea in 2019 identified VMS base metal sulphides in the footwall of the nickel sulphide stratigraphy. This is most favourable in terms of komatiite channel nickel sulphide models.
Ardea is continuing the assessment of the historic data from the region with the assistance of leading nickel sulphide and EM consultants Newexco. A pipeline of nickel sulphide exploration targets have been defined, with follow-up work currently under way. The top priority targets are two off-hole EM conductors that could represent high grade, Silver Swan style nickel sulphide occurrences.
A large number of gazetted gold occurrences are noted to the west of Ardea’s Kalpini project, mainly associated with the crustal-scale Emu Fault. Additionally, there are historic gold occurrences within Ardea’s tenements, with the area primarily assessed as a nickel-cobalt laterite project and nickel sulphide exploration opportunity in the past. As a result of this, assaying historic drill samples for gold has been extremely limited, with Ardea now the first to do so.
Perrinvale nickel sulphide and gold prospect
Perrinvale is located approximately 100km west of Leonora. The Ardea exploration model is based on recent nickel sulphide discoveries immediately west of Perrinvale made by St George Mining. Regional magnetic data highlights that the feature which hosts the St George Mining nickel sulphide discoveries within the Cathedrals Belt, has an east-northeast strike and extends into Perrinvale. At Perrinvale, this prospective trend is overlain by transported cover, requiring geophysical methods such as moving loop Electro Magnetic (MLEM) surveys for exploration targeting.
MLEM surveys have been completed by Ardea over three separate zones at Perrinvale with a consultant’s field report received during the December 2019 Quarter which recommended follow-up exploration including shallow aircore drilling beneath transported cover to determine basement geology and the geochemical signature associated with the EM anomalies defined. Surface EM surveys were recommended over the areas not covered by the initial trial survey.
A gold targeting review was completed by Ardea and reaffirmed that the eastern part of the tenure overlies poorly exposed greenstones along the northern extension of the Zuleika Shear system, which is a known gold-bearing structure at Kundana, south of Ardea’s tenure. The fact that there are no gazetted gold occurrences over the greenstone belt within Ardea’s tenure is believed to be a function of the surface cover hiding the prospective basement rocks.
An internal review of geophysical datasets, focused predominantly on the interpretation of aeromagnetic data, has defined a number of gold exploration targets which have been ranked and added to Ardea’s ranking system and represent regional targets that would be best explored with wide spaced RAB or Aircore drilling through the surface cover for geological logging and geochemical sampling. This data would then be used to help vector in on any bedrock gold anomalism defined, targeting a greenfields discovery.
Bulong and Taurus gold prospect
Ardea’s Bulong tenements are located approximately 30km east of the City of Kalgoorlie Boulder. The regionally significant crustal scale gold-controlling structure, the Goddard Fault, trends north-south and passes through Ardea’s Bulong tenure. This structure represents a northern splay of the regionally significant Mount Monger Fault, which hosts gold mineralisation to the south, with the best-known operating mine in the area at Daisy Milano.
Historically, the focus on the Bulong tenements has been on high grade laterite hosted nickel-cobalt mineralisation (54.1Mt at 0.88% Ni and 0.05% Co, for contained metal of 476.1kt nickel and 28.8kt cobalt) as part of the KNP resource base, with minimal historical gold exploration.
Ardea commenced systematic gold exploration with a detailed mapping and sampling program around the historic Taurus underlay shaft and multiple workings in the area. Fifty four rock chip samples were collected during the mapping program with 22 samples (40%) 1g/t Au or greater and the average grade for all samples collected in this program was 4.86g/t Au. This program has refined the controls on gold mineralisation in the project area.
Mapping has identified several other possible Taurus lode repeats as well as providing orientation and shear sense indicators. This information will be used to complement historic drill data, which is presently being compiled in detail, and other historic datasets. 3D models will be constructed from these datasets to enable definition of drill targets.
Ardea works with Kalgoorlie-Boulder prospectors who have been recovering alluvial, eluvial and primary gold in the area which is assisting with Ardea target generation and furthering the understanding of the controls on Bulong gold mineralisation.
In addition to the significant nickel-cobalt resources hosted at Bulong, 36 exploration targets have been defined. These range from gold, PGEs and base metals (nickel, copper, lead and zinc).
Limited historic nickel-cobalt laterite drill holes have been located over some of the gold targets and a search for the historic pulps within Ardea’s West Kalgoorlie sample archive facilities has been completed and samples submitted for multi-element assay, including gold for the first time. This is a low impact and much cheaper form of exploration, as it removes the need to redrill holes.
Mulga Plum gold and VMS base metal-sulphur prospect
The Mulga Plum gold prospect is a gold and base metal VMS target located 40km NE of Menzies and immediately SW of the historic gold mining town of Kookynie. The exploration model being tested by Ardea is a bulk tonnage granitoid gold system.
A review of historic data along with detailed mapping and rock chip sampling to confirm and extend historic gold anomalism was used to refine targets for RC drill testing. Drilling commenced on 12 December and before a hiatus for the Christmas break, a total of 20 RC holes for 1,148 metres was completed and 640 samples submitted for multi-element analysis.
Logging of RC drill chips has confirmed widespread disseminated sulphides across several alteration zones (propylitic epidote and potassic biotite dominant) and favourable rock types, including granitoid, mafic and felsic porphyry intrusives. Increased sulphides were also noted within the granite and along the base of mafic units. Assay results are required to help determine the significance of these observations as they relate to gold mineralisation.
A total of five holes for 350 meters remain to be drilled for completion of the program, which is scheduled to recommence in mid-January 2020.
Mt Zephyr Gold-Nickel Project (ARL 100%)
The Mt Zephyr Gold-Nickel Project is located in the Eastern Goldfields of Western Australia, another one of Australia’s great mineral provinces.
The Mt Zephyr-Darlot East metallogenic model for Ardea’s 910km² tenement holding is:
- The gold structural target is the shallow east-dipping Celia Lineament and 10km to the east (regionally from north to south localises the Jupiter, Wallaby, Sunrise Dam gold mining centres).
- Syenite-host, Ardea assaying confirms an alkaline igneous association with distinctive Ba-Sr-Ce-La-Nd association, alteration is dominantly pyrite with subordinate sericite, and alteration chemistry dominantly anomalous As-Mo-W.
The Mt Zephyr project continues to be reviewed, with multiple early stage targets defined at the Gale gold, Jones A nickel sulphide and Dunn’s Line gold prospects. Ardea needs to consider the best strategy for this quality tenement portfolio with current options including introducing a joint venture partner with a strong balance sheet and track record of exploration success to accelerate this opportunity without impacting Ardea’s tight capital structure and cash balance.
Mt Zephyr contains both primary gold and nickel mineralisation and encapsulates more than two thirds of an underexplored greenstone belt called Celia Lineament. The area east of the Celia Lineament is considered highly prospective for the following reasons:
- All historic gold workings east of lineament
- Mt Windarra nickel sulphide stratigraphy
- Jupiter, Wallaby granitoid-hosted gold to the east of the lineament further south
- Along structure from Mt Morgans, Lake Roe gold deposits
- Ardea are the first to test the new geological setting concepts
- First pass drill programs completed
- Gold at Gale, Dunn’s North, Dunn’s Line and Paul’s Find
- Ni-Cu sulphides (+ gold) at Jones Area A
- First-pass, wide-spaced (160mx160m) drilling confirms granite hosted gold mineralisation, at Gale
- Granitoid-hosted gold mineralisation from surface, limited drilling
- On Celia Shear Zone along strike from geologically similar Jupiter, Wallaby gold mines
- Outcropping gold-mineralised granite:
- Exceptional 900 x 300 m outcrop-limited anomaly at gold over 0.1 g/t (up to 1.49 g/t at surface)
- Sericite, pyrite, hematite alteration
- Gold, arsenic, copper and barium anomalism
- First-pass, wide-spaced (160x160m) drilling very promising:
- Intercepts include:
- AMZR0006: 96.00 m @ 0.28 g/t Au from 2 m
including 22.00 m @ 0.48 g/t Au from 10 m
- AMZR0002: 22.00 m @ 0.25 g/t Au from 6 m
including 4.00 m @ 0.79 g/t Au from 6 m
- AMZR0006: 96.00 m @ 0.28 g/t Au from 2 m
- Open in all directions
- Targets defined
- Near 100m intercepts are a rarity from a first pass exploration program and are interpreted as the distal, outlying halo of a significant gold mineralising system
- Parallels with Dacian’s Jupiter mine & Gold Fields’ Wallaby mine
Bedonia gold and nickel sulphide
The metallogenic model at Bedonia is nickel sulphide and Platinum Group Metals (PGM) associated with the Proterozoic-aged Jimberlana Dyke, with mineralisation at a historic prospect, Mordicus, as the proof of concept. Field programs by Ardea have identified targets at the Cleanthes and Lila gold prospects (historic drilling up to 2.7g/t Au), located on the Cundeelee Fault at the Albany Fraser Province western boundary.
Soil auger drilling programs have been designed and heritage clearance programs have been sought.