The company has released results from 43 holes from the campaign, including the latest assays from 13 holes in the central part of the Kobada deposit. The closer-spaced drill data in this area of the deposit is expected to increase the confidence in future resource estimations, potentially leading to a lift in inventories to feed into mining studies.
Management highlighted the presence of higher-grade zones recognised through the drilling, including the 10m interval at 4.37g/t gold and another 4m hit at 6.34g/t. It added that such zones had frequently been intersected in historical drilling at Kobada, with increased drilling density in the current campaign potentially paving the way for a boost in the upcoming resource estimate.
Toubani Resources chief executive officer Phil Russo said: “Kobada’s potential is clearly evident in our drilling to date as momentum in the resource definition program continues to build. Our confidence is growing in demonstrating Kobada as one of the few remaining, if not the sole, advanced-stage, large-scale, oxide gold projects in the hands of a single-asset developer, with the delivery of an updated feasibility study later this year.”
The company’s tenure in Mali covers a 136-square-kilometre mining permit that is valid through to 2045, in addition to two adjacent exploration concessions. It also incorporates an environmental permit granted in 2021, which relates to production of oxide ores at the project.
Management is now looking to amend its terms to also integrate the development and mining of the sulphides portion of its Kobada deposit. Notably, gold mineralisation at Kobada is hosted in Birimiam greenstones renowned for holding several multi-million-ounce gold deposits in Mali and its bordering nations.
The main deposit at Kobada extends for more than 5km in length, with the existing resource estimate defined within a planned 4.5km-long open pit. It totals 87 million tonnes at 0.84g/t for the 2.4 million ounces of gold.
Kobada is predominantly an oxide system and remains open along strike in two directions. Mineralisation has been defined to 250m below the surface and remains open at depth. All up, some 77 per cent of the current mineral resource lies within the first 150m beneath the ground.
Oxide mineralisation at the deposit averages 65m depth and extends beyond 120m in some areas of the proposed pit, comparing favourably with other oxide gold deposits found in West Africa.
Management believes the soft oxide ore makes the project suitable for a straightforward mining and processing operation, with more appealing economics than hard rock gold deposits.
According to Toubani, a bulk-tonnage oxide mining and processing venture represents a lower technical risk profile since mining methods applicable at the project do not need to be highly selective. It also requires minimal drilling and blasting, with crushing and grinding circuits being simplified to make them less power intensive.
Such traits could result in lower operating costs.
About 85 per cent of the first 100m depth in the resource estimate is characterised as oxide material, resulting in a low stripping ratio. However, additional upside also exists below the oxides, with nearly one million ounces of gold found in the deeper fresh rock.
Management notes that other significant gold mines in West Africa, such as AngloGold Ashanti’s nearby Siguri project just across the border in neighbouring Guinea, started their production journeys with a successful oxide operation. More than 9 million ounces of gold have been defined at Siguri.
The upcoming DFS for Kobada is designed to assess the merits of an oxide-dominant operation, characterised by reduced operating costs and a moderate capital outlay. Works related to the update kicked off in July last year, with the company looking to build on the outcomes from its 2021 DFS that envisaged an operation with a substantially bigger quantity of mined ore than processed ore in the first 10 years of production.
In turn, substantial stockpiles were anticipated to be amassed, impacting cashflows and requiring double handling later in the project life.
A 16-year mine life was estimated for Kobada, with the project anticipated to churn out at least 100,000 ounces of gold per annum in the first decade of production. An additional five years was then committed to stockpiles built up during the first 10 years.
The upcoming DFS is focused on a range of higher processing plant throughputs, coupled with optimised mining schedules and stockpile balances. It incorporates a bigger bulk mining equipment fleet than was envisaged in the 2021 study and seeks to increase annual production rates, reduce unit costs, bring cash flows forward and remove rehandling costs.
Separately, Toubani’s landholding in Mali also boasts the potential for major exploration upside despite a significant gold system already being defined at the tenure.
More specifically, exploration drilling from last year identified new areas of gold mineralisation across five targets sitting outside the existing resource base. New areas of significant oxide mineralisation were intercepted at all five prospects, with the strike length of the main deposit growing from 5km to 11km.
Some notable hits from the exploration drilling include 9m at 1.72g/t gold at the Kobada West prospect, interpreted to lie on a parallel structure less than 1km from the project’s main deposit. The intercept also contains a richer 2m zone grading 6.26g/t gold.
Drilling at the Kobada North 1 and North 2 targets also delivered some serious intercepts including 9m at 1.32g/t and 14m at 1.02g/t gold in one hole.
Those results appear to bode well for Toubani’s future exploration works, suggesting a much bigger gold system could be lurking beneath the ground. Curiously, about 40km of the 50km of regional-scale shear zones at the tenure are yet to be tested with the rig.
If other Malian gold mining operations are anything to go by then it would not be a big surprise to see the resource base at Kobada continue to grow.
Major international mining companies have been digging up gold in Mali for decades, including the world’s second-biggest producer of the precious yellow metal, Barrick Gold. Barrick runs two gold mines in the nation at its 11-million-ounce Loulo project and the 5.1-million-ounce Gounkoto operation.
Its Canadian counterpart Allied Gold churns out nearly 200,000 ounces of gold each year from its Sadiola project where a whopping 13 million ounces of gold have been defined. Renowned ASX-listed miner Resolute Mining also calls Mali home at its 10.5-million-ounce Syama project.
Notably, the plethora of multi-million-ounce gold deposits in Mali are all contained within the same Birimian greenstones that host the mineralisation at Kobada.
Toubani has unveiled a major gold system at Kobada and could be on its way to a compelling resource update due for release in the coming weeks. So, the next few months could be transformational for the West Perth outfit, with results from a DFS set to follow just as the price of the precious yellow metal threatens to fly into orbit.
Just last week, the gold price hit a record high after exceeding US$2400 (AU$3702) per ounce.
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