Coda Minerals Reports Updated Economics Following Flowsheet Modifications

• Process change: Whole-ore leach flowsheet achieves 95% copper and 98% silver recoveries compared to 83% and 82% from flotation method
• Financial metrics: Pre-tax NPV of $1.29 billion and 39% IRR, increasing to $1.81 billion and 48% IRR at spot prices
• Capital reduction: Total CAPEX decreased by $74 million to $615 million with payback period of 3.25 years
• Production increase: Life-of-mine output of 454,000 tonnes copper and 20 million ounces silver versus previous 384,000 tonnes and 16 million ounces
• Cobalt repositioning: Metal excluded from base case economics, treated as potential future upside rather than core requirement

Coda Minerals (ASX:COD) is an Australian exploration and development company focused on discovering and developing base and battery metals, with its flagship asset being the Elizabeth Creek Copper-Cobalt Project in South Australia. The project comprises four deposits: Emmie Bluff, MG14, Windabout, and Cattle Grid South. The company holds 100% ownership of the project through its tenements in the region.

The Elizabeth Creek Project contains mineral resources across multiple deposit types. Three deposits (Emmie Bluff, MG14, and Windabout) are classified as Zambian-style sediment-hosted copper deposits, while Cattle Grid South represents breccia-hosted mineralisation. The project has access to existing infrastructure including the Stuart Highway and Adelaide-Darwin rail line.

Metallurgical Flowsheet Changes and Recovery Improvements

The revised processing approach eliminates flotation concentration and the Albion Process oxidation circuit previously required for the project. The new whole-ore leach method uses chloride leaching in a single-stage oxidative circuit with four-hour processing time at 90 degrees Celsius. Ore grinding requirements are reduced from 32 micrometres to 75 micrometres.

Copper recovery rates increased from 82.8% to 94.8% while silver recoveries improved from 82% to 98.2% under the modified process. The company conducted test work on samples from three drill holes at the Emmie Bluff deposit, with core material stored in sub-zero conditions since 2021 to prevent oxidation. Chloride leaching technology has been used commercially for approximately two decades at operations including Chile's Michilla, Centinela, and Zaldívar mines.

The process uses standard hydrometallurgical circuits for product recovery, including solvent extraction and electrowinning for copper cathode production, Merrill Crowe processing for silver doré, and precipitation for zinc carbonate. All reagents proposed are described as widely available and low cost, with anticipated high recyclability for chlorides used during leaching.

Project Economics and Cost Structure

The updated economic model reports pre-tax NPV of $1.29 billion and IRR of 39% using base case commodity prices of $9,260 per tonne copper and $30 per ounce silver. Post-tax figures show NPV of $855 million and IRR of 30%. At current spot prices ($9,718 copper, $39 silver), pre-tax NPV rises to $1.81 billion with 48% IRR.

Total project CAPEX decreased by $74 million to $615 million, comprising $472 million pre-production and $143 million post-production capital. The reduction stems from eliminating flotation and oxidation circuits while adding whole-ore leach infrastructure. Processing operating costs fell by $7.50 per tonne, representing a 19% decrease from the previous flowsheet.

Annual steady-state production is estimated at 31,400 tonnes copper and 1.4 million ounces silver over a 15.5-year mine life. The all-in sustaining cost is calculated at $2.15 per pound copper. The company projects total lifetime contributions of $253 million in state royalties and $705 million in federal taxes.

Development Approach and Technical Considerations

The revised base case removes cobalt production from initial economic calculations while maintaining the metal as potential future integration. CEO Chris Stevens noted:

"Cobalt represents further upside for the project, with the potential for critical minerals incentives and funding support, but crucially it is no longer required for the base case economics".

Mining plans remain unchanged from previous studies, with MG14 and Windabout designated for open-pit extraction and Emmie Bluff scheduled for underground development using mechanical cutting methods. The production schedule spans 18 years across four deposits, with 87% of feed sourced from Indicated Resources and 13% from Inferred Resources. Cattle Grid South mining is scheduled for the final years of operation.

The company acknowledges that metallurgical results are preliminary and based on early-stage test work. Additional variability testing is required across all deposits, and CAPEX and OPEX estimates are derived partly from modifications of earlier calculations. Both whole-ore leach and flotation processing methods will be evaluated during the ongoing Pre-Feasibility Study to determine the final development approach.

Ongoing Work and Study Timeline

Coda continues metallurgical test work focusing on cobalt recovery pathways and process optimisation. The company expects to integrate selected cobalt recovery methods into the current flowsheet model and update CAPEX and OPEX estimates accordingly. Additional variability testing will be conducted across the broader Elizabeth Creek project including the MG14, Windabout, and Cattle Grid South deposits.

The revised copper-silver base case will be incorporated into the ongoing Pre-Feasibility Study, with both processing options carried forward for final economic comparison. The company maintains that completion of cobalt test work will largely determine the final whole-ore flowsheet design, with updated economic assessments to follow.

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