Cobra's Manna Hill Step-Out Adds 2 Porphyry Targets Beyond Blue Rose

• Cobra Resources has scheduled a September reverse circulation (RC) step-out at its Manna Hill copper project in South Australia, testing the Blue Rose skarn alongside 2 porphyry targets generated from state-based radiometric datasets.
• Round Hill pairs a uranium anomaly with copper at the surface; Welsh Prince is defined by a non-coincident thorium-uranium anomaly.
• Diamond drilling completed before the step-out logged hydrothermal breccia over more than 50 meters (m), anhydrite veining, and bornite-bearing potassic alteration, the vectors that point to a porphyry source beneath the skarn.
• Copper mineralization at Blue Rose now extends to a depth of 300 meters, beneath RC holes that returned 86 86 meters at 0.60% copper and 0.14 grams per metric ton (g/t) gold, and 74 meters at 1.02% copper and 0.25 g/t gold.
• Anabama and Netley Hill, both with existing porphyry-style intersections, are scheduled for drilling after Blue Rose, and regional targets are scheduled into 2027.

Cobra Resources (LSE: COBR) is broadening its South Australian copper drilling from 1 deposit to a ranked list of targets. A reverse circulation (RC) step-out planned for September at the Manna Hill project will test the Blue Rose skarn alongside 2 porphyry targets, Round Hill and Welsh Prince. For a company whose copper story has so far been told through a single set of shallow intersections, the program shows which geological signals Cobra weighs before it commits meters.

What the September Program Tests

State-based radiometric datasets across Manna Hill highlight large uranium and thorium anomalies, which Cobra interprets as a marker of hydrothermal alteration. Round Hill pairs a uranium anomaly with surface copper. Welsh Prince is defined by a non-coincident thorium-uranium anomaly. Both are in the September step-out.

They join 2 older porphyry prospects that are already backed by drill intersections. Netley Hill has returned 350 meters (m) at 0.1% copper, 0.015% molybdenum, and 1 gram per metric ton (g/t) silver, plus 24 meters at 0.3% copper and 0.02% molybdenum. Anabama has returned 27 meters at 0.2% copper and 24 meters at 0.06% molybdenum, alongside 9 meters at 0.4% copper. Both are scheduled for drilling after Blue Rose, with heritage clearance, soils, and geophysics ahead of a regional drilling program scheduled into 2027.

The Vectors Behind the Target List

The vector set came out of the diamond drilling completed before the step-out. That drilling logged hydrothermal breccia over more than 50 m, from 350 m to 402 m depth; anhydrite veining from 199 m to 220 m; coarse chalcopyrite in potassic alteration at 195 m depth; and bornite veining from 220 m to 230 m. Cobra treats breccia thickness, anhydrite veining and copper-potassic mineralization at depth as the vectors pointing toward a porphyry source beneath the Blue Rose skarn.

The copper minerals themselves differ in grade. Chalcopyrite contains 30% to 33% copper; bornite contains more than 60%, and its presence within a potassic halo places the hole closer to the heat source. Managing Director of Cobra Resources, Rupert Verco, described what that change implied for the scale of the system:

"So, this is showing us that the mineralization system extends beyond the skarn and into a much greater porphyry system." 

Anhydrite does the same work from a different direction. Verco set out why a barren mineral earns a place on the list:

"These things are not generally mineralized, but they're very important because they are the source of mineralization that's coming into that skarn."

Blue Rose Still Holds the Grade

The drilled part of the project remains the grade anchor. Blue Rose and Neptune Rose have returned 47 meters at 2.2% copper and 0.78 g/t gold from 11 meters, 74 meters at 1.02% copper and 0.25 g/t gold from 70 meters, and 86 meters at 0.60% copper and 0.14 g/t gold from 18 meters. Cobra drilled Blue Rose first in January 2026, and the diamond holes that followed extended copper mineralization to a depth of 300 meters, below the RC holes that produced those intersections. 

The diamond campaign also cost the company a target. Cobra had planned roughly 1,800 meters, including 2 holes at Black Rock, where a coincident chargeable and resistive anomaly is present. The first Black Rock hole reached about 440 meters and intersected a potassic zone with light chalcopyrite, but the intensity of the pyrite there led the company to drop the second hole and put those meters into deeper skarn holes instead. Total drilling came in slightly under 1,500 meters. One diamond hole was drilled from the south and intersected shallow copper oxide, opening an extension to the south of the skarn. 

Assays from that diamond drilling are pending. Petrology and petrophysics work is underway to understand how reverse magnetism affects geophysics before the next round of targeting.

Project & Regional Context 

Cobra has built out the technical bench around Manna Hill. Stephen McIntosh, with more than 40 years in global resources, including 33 at Rio Tinto and advisory roles at Andina Copper and Chalice Mining, joined as technical and strategic advisor. Professor Ross Large AO performed the 2026 geochemical analysis behind the Blue Rose model. Andrew Michelmore AO, former chief executive officer of WMC, OZ Minerals, MMG, and Zinifex, chairs the board. 

At 4.2p on August 18, 2026, across 1,085,653,414 ordinary shares, Cobra had a market capitalization of £47.7 million, with 211 million warrants outstanding at 2.0p, 2.3p and 6.0p. Non-dilutive capital comes from the 2025 sale of the company's non-core gold assets, which leaves Cobra holding 6.45 million Barton Gold shares at final settlement, plus A$9.5 million in further future payments. Copper is 1 of 2 legs: the Wudinna rare earths project in the same state is working toward a maiden mineral resource estimate, the company has said it expects to announce shortly, followed by scoping study updates. 

That split is the investment case and the risk in one. A junior funding 2 development stories on a £47.7 million market capitalization has to choose where each rig goes, and the September program sets that order from Manna Hill's target list, not from a single deposit. Confirmation depends on 2 results arriving in sequence: assays from the diamond holes, then the first intersections from Round Hill and Welsh Prince. 

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