Ausquest Ltd
AusQuest Extends Coober Pedy IOCG Drilling Program as Basement Results Await Assay
Ausquest Ltd (ASX: AQD) has reported that its maiden Reverse Circulation (RC) drilling program at the Coober Pedy Iron-Oxide Copper-Gold (IOCG) Project in South Australia has been partially completed, with three of the planned 15 drill-holes reaching the targeted basement rocks. The AusQuest Coober Pedy IOCG drilling update and assay results reveal that drilling was halted after seven holes due to challenging near-surface conditions, and the program is now scheduled to resume in Q3 CY2026 with a different drilling method and a new contractor.
According to the ASX announcement dated 26 June 2026, assay results from the three completed holes are expected by the end of July 2026. The project is located at the northern end of the Olympic Dam IOCG Province and is held under a Strategic Alliance Agreement (SAA) with a wholly-owned subsidiary of South32 Ltd.
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What Happened Underground: Current Drilling Status
The initial RC program at Coober Pedy was designed as a 15-hole test of priority geophysical targets. In practice, only seven RC holes were drilled before the contractor was forced to stop due to difficult ground conditions above the basement rocks.
A thick, dry, unconsolidated quartz sand unit, about 30 metres thick and situated immediately above the basement, prevented four of the seven holes from reaching their target depth. Standard RC drilling struggled to progress through this material.
The outcome of the seven holes reported in the ASX announcement can be summarised as follows:
| Hole ID | Depth (m) | Basement reached? | Logged basement rock type |
|---|---|---|---|
| 26CPRC001 | 354 | Yes | Intermediate gneiss |
| 26CPRC002 | 90 | No | Did not reach basement |
| 26CPRC003 | 78 | No | Did not reach basement |
| 26CPRC004 | 90 | No | Did not reach basement |
| 26CPRC005 | 60 | No | Did not reach basement |
| 26CPRC006 | 216 | Yes | Granite |
| 26CPRC007 | 174 | Yes | Intermediate gneiss |
The three holes that successfully intersected basement rocks are:
- 26CPRC001 – 354 m total depth, intermediate gneiss
- 26CPRC006 – 216 m total depth, granite
- 26CPRC007 – 174 m total depth, intermediate gneiss
Two of these holes, 26CPRC001 and 26CPRC007, are located at the Bulldog prospect, about 400 metres from historical Vale drill-hole GAWRC001, which is reported to have intersected strong potassic alteration beneath the cover. According to Ausquest Ltd, both Bulldog holes recorded:
- Mafic to intermediate gneissic rocks
- Occasional pink granitic dykes
- Variable chlorite alteration
- Up to 5% sulphides (mainly pyrite) in some intervals
These observations are geological, not assay-based, and no grades have been reported at this stage. Assays from the three completed holes are expected by the end of July 2026, using multi-element analysis and 50 g fire assay for gold at Intertek in South Australia.
"The Coober Pedy Project remains an important focus for AusQuest due to the highly prospective nature of the rocks in the area. We look forward to receiving the results from the first three holes in the coming weeks and completing the planned drilling program a little later this year," said Graeme Drew, Managing Director of Ausquest Ltd.
Solving the Sand Problem: Shift to Mud Rotary Drilling
The primary technical challenge encountered in the maiden program was the unconsolidated quartz sand unit above basement. Because this unit is dry, loose and relatively thick, conventional RC drilling with air return was not able to maintain hole stability or penetration in four of the seven holes.
In response, Ausquest Ltd is engaging a second drilling contractor and changing the drilling methodology to a mud rotary system for the upper part of each hole. The planned sequence is:
- Use mud rotary drilling through the loose sand unit.
- Case off this interval to stabilise the hole.
- Complete the hole to the planned depth of about 350 metres using RC drilling or diamond drilling, depending on conditions and objectives.
Mud rotary drilling uses a fluid to carry cuttings to the surface and support the hole walls in weak or unconsolidated formations. This approach is widely used in sedimentary cover where air-based RC methods struggle.
According to the ASX announcement, drilling is planned to re-commence in Q3 CY2026, once a suitable rig is secured. The company then aims to complete at least another 10 drill-holes to test target areas defined by magnetics, gravity and Induced Polarisation (IP) surveys.
For investors, this change in drilling method is relevant because:
- It indicates that the principal issue to date has been engineering, not geology
- It provides a pathway for Ausquest Ltd to complete the remaining ~12 holes of the original 15-hole concept
- It allows the program to continue to test the geophysical anomalies that formed the basis of the initial targeting
Educational Section: Understanding IOCG Mineralisation
What Is an IOCG Deposit?
Iron-Oxide Copper-Gold (IOCG) deposits are large mineral systems that contain:
- Copper and gold as primary economic metals
- Abundant iron oxides, such as magnetite and haematite
- A range of other possible by-products, which can include uranium and rare earth elements, depending on the system
They often form deep in the crust, where hot, metal-rich fluids move through rocks and deposit metals in zones of structural weakness and chemical contrast.
The Olympic Dam IOCG Province, where the AusQuest Coober Pedy IOCG drilling update and assay results programme is operating, hosts some of the world's best-known examples of this deposit type. The Coober Pedy Project sits within the Mount Woods Domain, where previous work has identified Hiltaba Suite granites and favourable alteration geochemistry, which can indicate fluid movement and metal transport.
Key Geological Terms in This Announcement
Basement rocks are older, hard crystalline rocks that sit beneath younger sediments or unconsolidated cover. In this context, the RC drilling is trying to reach these basement rocks to test for IOCG-style alteration and sulphides.
Gneiss is a high-grade metamorphic rock formed under intense heat and pressure, whilst granitic dykes are thin, sheet-like intrusions of granite that cut through other rocks. Both can act as hosts or pathways for mineralising fluids in IOCG systems.
Chlorite alteration means that the rock has been changed by hot fluids, which can be associated with mineral systems, including IOCG. Furthermore, potassic alteration refers to rocks enriched in potassium-bearing minerals such as K-feldspar or biotite, and is often considered an important indicator in many IOCG environments.
Why Does Sulphide Content Matter?
Sulphide minerals contain sulphur combined with metals, for example pyrite (iron sulphide) and chalcopyrite (copper-iron sulphide). The presence of up to 5% sulphides in the Bulldog holes suggests a hydrothermal system, however the economic significance depends on which metals are present, their grades from assays, and the size and continuity of any mineralised zones.
At Coober Pedy, no assay results for metals have yet been published, so there is currently no information on grade or economic potential.
Why IOCG Systems Matter to Investors
From an investment perspective, IOCG projects attract attention for several reasons:
- They can be very large in terms of contained metal
- They often require deep drilling under cover, which makes exploration high-risk but potentially high-impact
- They rely heavily on geophysics (magnetics, gravity, IP) to identify targets before drilling, because mineralisation is typically not exposed at surface
In the Coober Pedy Project, Ausquest Ltd has completed regional and detailed geophysical surveys, used these to define drill targets at Bulldog, and commenced a multi-hole drilling program to test whether geophysical anomalies are associated with altered, sulphide-bearing basement. The early observations are consistent with a hydrothermal system, but only assays and further drilling will clarify whether any economic mineralisation is present.
Sampling, Assays and Data Quality
The ASX announcement includes a JORC Table 1 summary describing how samples and data are being collected and handled, providing important context on data quality for investors assessing Ausquest Ltd.
Sampling and Assaying Approach
Key points include:
- Drilling method: Reverse Circulation (RC) with a face-sampling bit, hole diameter about 132 mm
- Sample intervals: one-metre samples collected at the rig, with composite 2 m samples formed using a static cone splitter, at about 2.5–3.5 kg per sample
- Laboratory: Intertek South Australia, a certified minerals laboratory
- Analytical methods: four-acid digest with ICP-MS for a broad suite of elements, including Cu, Au pathfinders and base metals, plus 50 g fire assay for gold
Quality control procedures include insertion of certified standards every 40th sample, use of laboratory standards, repeats and blanks, and review by Ausquest Ltd to check for bias or issues. This framework is typical for early-stage base metals and gold exploration.
Forward Program: Q3 2026 Drilling and Key Milestones
According to the announcement, Ausquest Ltd has outlined a clear sequence of upcoming activities at Coober Pedy:
- Assay results from completed holes – Holes 26CPRC001, 26CPRC006 and 26CPRC007, expected by the end of July 2026, covering multi-element ICP-MS and gold assays.
- Recommencement of drilling – Timing of Q3 CY2026, depending on rig availability, using mud rotary to get through the sand unit, then RC or diamond drilling to about 350 m.
- Planned drilling coverage – At least 10 additional holes, spaced approximately 200–400 metres apart, aimed at building a geochemical and geological picture across priority target zones.
- Ongoing interpretation – Integration of assay data with magnetic, gravity and IP datasets, and assessment against IOCG models in the Mount Woods Domain.
A summary of near-term milestones is set out below:
| Upcoming activity | Details | Expected timing |
|---|---|---|
| Assay results from 3 RC holes | Multi-element ICP-MS and 50 g fire assay for gold | End of July 2026 |
| Engagement of new drilling contractor | Mud rotary pre-collar, RC/diamond tails | Q3 CY2026 |
| Restart of drilling operations | Completion of remaining target holes to ~350 m | Q3 CY2026 |
| Completion of at least 10 further holes | Testing geophysical anomalies across project area | Q3/Q4 CY2026 |
For investors following Ausquest Ltd, these steps define the likely sequence of news flow over the second half of 2026.
Investment Context: Why Coober Pedy Remains on the Radar
From the information provided in the ASX announcement, several aspects of the Coober Pedy Project may interest resource-focused investors:
- Location in a recognised IOCG province – The project lies at the northern end of the Olympic Dam IOCG Province, within the Mount Woods Domain, an area with known iron oxide alteration and Hiltaba Suite granites.
- Systematic target generation – Ausquest Ltd has followed a staged approach, moving from government and historical data to company geophysics and prior drilling by groups such as CRA, BHP, Teck and Vale, and then to the current RC drilling program.
- Presence of alteration and sulphides – The intersected gneissic and granitic rocks at Bulldog show chlorite alteration and up to 5% sulphides in places, indicating fluid movement and mineral deposition.
- Adaptation of drilling strategy – The shift to mud rotary pre-collars reflects a technical response to ground conditions rather than a change in geological concept.
- Partnership with a South32 subsidiary – The project is operated under a Strategic Alliance Agreement with a wholly-owned subsidiary of South32 Ltd, which may suggest alignment with the exploration priorities of a larger mining group.
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Why Investors May Continue to Watch Ausquest Ltd at Coober Pedy
The AusQuest Coober Pedy IOCG drilling update and assay results position Ausquest Ltd at an early-stage but important phase of exploration. The key points for market participants include:
- Near-term assays – Geochemical results from the first three basement-intersecting holes are expected by the end of July 2026, providing the first direct multi-element dataset from targeted basement rocks in this program.
- Majority of drilling still ahead – Only 3 of the planned 15 holes have been completed to target depth, with at least 10 further holes planned.
- Clear geological rationale – Drilling is focused on anomalies supported by magnetics, residual gravity and IP, located close to historical intersections such as Vale's GAWRC001 at Bulldog.
- Operational response in place – By altering its drilling method and contractor, Ausquest Ltd has set out a practical way to address the cover sequence challenge and continue its basement testing program.
For investors focused on early-stage copper-gold exploration in established provinces, the next phases at Coober Pedy represent an evolving dataset that will help clarify the geological potential of Ausquest Ltd's project area.
Want to Know More About AusQuest's Coober Pedy IOCG Project?
With assay results from the first three basement-intersecting holes expected by the end of July 2026 and at least 10 further drill-holes planned for Q3/Q4 CY2026, AusQuest Ltd (ASX: AQD) is approaching a significant period of news flow at its Coober Pedy IOCG Project. Investors seeking to learn more about the company, its strategic alliance with a South32 subsidiary, and the broader exploration programme underway in the Olympic Dam IOCG Province can visit the official AusQuest website at www.ausquest.com.au.