Cobra Confirms Blue Rose Porphyry Indicators, Starts 52-Hole Drill Program

• Diamond drilling below the Blue Rose skarn at Cobra Resources' Manna Hill copper project in South Australia returned copper-gold intersections, molybdenum, and hydrothermal breccias, all typical of the upper parts of a porphyry system.
• One hole returned 23 meters (m) at 0.63% copper and 0.09 grams per metric ton (g/t) gold from 186 m, including 12.4 m at 1.01% copper and 0.13 g/t gold.
• A second hole returned 16.9 m at 0.08% molybdenum from 335.5 m, in altered wall rock contacting a hydrothermal breccia.
• Mineralized intervals extend beyond 300 m downhole in both assayed holes and remain open.
• Up to 6,000 m of reverse circulation (RC) drilling across 52 holes is underway, targeting extensions of the Blue Rose strike and testing the Netley Hill and Anabama prospects.

Cobra Resources (LSE: COBR) has reported the first assays from diamond drilling below the Blue Rose skarn at its Manna Hill copper project in South Australia. Results from 2 of 4 holes returned copper-gold intersections, molybdenum mineralization, and hydrothermal breccias, all 3 typical of the upper parts of a porphyry system. Up to 6,000 meters (m) of reverse circulation (RC) drilling across 52 holes and 4 prospects is now underway, targeting strike extensions at Blue Rose and testing the Netley Hill and Anabama prospects.

What the September Program Tests

Netley Hill and Anabama, both porphyry prospects already backed by drill intersections, are in the program alongside Blue Rose. Netley Hill has returned 350 m at 0.1% copper, 0.015% molybdenum, and 1 gram per metric ton (g/t) silver, plus 24 m at 0.3% copper and 0.02% molybdenum. Anabama has returned 27 m at 0.2% copper and 24 m at 0.06% molybdenum, alongside 9 m at 0.4% copper. Drilling is targeted to run for 6 weeks from late September, with results to follow.

State-based radiometric datasets across Manna Hill highlight large uranium and thorium anomalism, interpreted as a marker of hydrothermal alteration. Round Hill, a porphyry target, pairs a uranium anomaly with surface copper mineralization. Welsh Prince, a second porphyry target, is defined by a non-coincident thorium-uranium anomaly. Cobra is targeting heritage clearance, soils, and geophysics ahead of a regional drilling program in 2027.

The Vectors Behind the Target List 

Diamond drilling below Blue Rose logged the vectors Cobra is using to locate a porphyry source beneath the skarn. The holes intersected 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. The breccia hole also returned 16.9 m at 0.08% molybdenum from 335.5 m, including 1.1 m at 0.48% molybdenum, in altered wall rock contacting the breccia. Molybdenum is a primary pathfinder, an element used to trace a nearby deposit, because it generally lies closer to the potassic alteration zone, which can host higher-grade copper.

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." 

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."

Diamond Assays Extend Blue Rose Copper Beyond 300 m

Shallow RC drilling at Blue Rose returned thick, high-grade intersections. Blue Rose and Neptune Rose have returned 47 m at 2.2% copper and 0.76 g/t gold from 11 m, 74 m at 1.02% copper and 0.25 g/t gold from 70 m, and 86 m at 0.60% copper and 0.14 g/t gold from 18 m. Cobra first drilled Blue Rose in January 2026, and the subsequent diamond holes were drilled beneath those RC intersections.

Management says Cobra had planned roughly 1,800 m of diamond drilling, including 2 holes at Black Rock, where a coincident chargeable and resistive anomaly is present. The first Black Rock hole reached about 440 m and intersected a potassic zone with light chalcopyrite, but the intensity of the pyrite there led the company to drop the second hole and instead put those meters into deeper skarn holes. Total drilling came to 1,465 m across 4 holes. Management also says a diamond hole drilled from the south intersected shallow copper oxide mineralization, which opens an extension to the south of the skarn.

Of the 4 diamond holes, 2 have been assayed. One returned 23 m at 0.63% copper and 0.09 g/t gold from 186 m, including 12.4 m at 1.01% copper and 0.13 g/t gold. The other returned 36 m at 0.39% copper and 0.05 g/t gold from 232 m, including 10 m at 0.99% copper, 0.13 g/t gold, and 0.02% molybdenum. Mineralized intervals in both holes extend beyond 300 m downhole and remain open. Assays from the remaining 2 holes are pending, along with petrology and petrophysical test work on all 4.

Project & Regional Context 

Cobra has built out the technical bench around Manna Hill. Technical and Strategic Advisor to Cobra, Stephen McIntosh, brings more than 40 years of global resources experience, including 33 years at Rio Tinto and advisory roles at Andina Copper and Chalice Mining. Geological Advisor to Cobra, Professor Ross Large AO, performed the 2026 geochemical analysis of Blue Rose drilling. Non-Executive Chair of Cobra Resources, Andrew Michelmore AO, is a former chief executive officer of WMC, OZ Minerals, MMG, and Zinifex.

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. The 2025 sale of the company's non-core gold assets for A$15 million in cash and shares leaves Cobra holding 6.45 million Barton Gold shares at final settlement, plus A$9.5 million in further future payments. The Wudinna rare earths project in the same state is working toward a maiden mineral resource estimate targeted for announcement shortly, followed by scoping study updates. 

What the Porphyry Vectors Mean for Manna Hill

Cobra is advancing 2 development projects on £4,021,223 of available cash as of June 30, 2026, sufficient to execute its planned exploration activities. The diamond assays add to the scale potential of Blue Rose, and the high molybdenum grades, beside a large hydrothermal breccia, are evidence of a much larger mineral system. The RC program underway follows up on that at Blue Rose strike extensions and at Netley Hill and Anabama, where earlier drilling has already intersected porphyry-style copper and molybdenum.

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