Aguia Resources has made a major geological breakthrough at its Santa Barbara gold project in Colombia, unveiling a potentially massive vein system. The discovery may prove to be a big interconnected stockwork of mineralisation, linking multiple deposits.
The revelation came after a new set of underground channel samples from an old-timers artisanal adit close to the company’s existing workings picked up a set of cross-cutting veins.
Standout channel sample results from the rediscovered adit came in at an impressive 18.6 grams per tonne (g/t), 16.49g/t and 9.51g/t gold, pointing to strong ties between the company’s existing Santa Barbara and Mariana vein systems.
The proximity of the new stockwork system to Aguia’s Santa Barabara and Mariana vein sets hints at a potentially much larger, multidirectional gold-bearing system than previously thought.
Management says the new vein, running almost due north with a steep southwest dip, could be the missing link between the company’s two main systems, mirroring the style of Colombia’s world-class Buriticá mine, which hosts 5.3 million ounces at 10.3 grams per tonne gold.
To date, 19 of 25 diamond drill holes totalling 2,027 metres have been sunk into the Santa Barbara and Mariana targets. The exploration program had been designed to unlock a potentially huge discovery within the company’s existing rich mesothermal vein network.
However, the discovery of a new vein set has prompted a serious rethink of its exploration focus, shifting the model from isolated lodes to a far more extensive, interconnected gold network. New drill plans are now in the mix to test strike-parallel orientations and chase down the full extent of the newly identified vein structures.
Aguia Resources executive chairman Warwick Grigor said: “The assay results from the newly discovered artisanal adit suggest a vein strike direction that clearly demonstrates the connection between the main vein sets being exploited at Santa Barbara. Additionally, the introduction of a totally new management team both corporately and operationally has had a very positive effect on the Santa Barbara operation.”
In the past two months the company has overhauled its entire Colombian operational management, ditching unskilled labour for seasoned in-country specialists with deep experience in narrow-vein mining and gold processing.
Since then, Aguia says it has seen dramatic improvement in both mine-grade control and plant recovery. Dilution has been slashed thanks to the adoption of more selective mining techniques and feed grades are now regularly clocking in above 10g/t gold.
On the processing front, Aguia’s plant is starting to hit its stride, with a series of savvy upgrades already delivering results, with even more changes in the pipeline to keep the momentum building.
By setting the mill discharge to a finer grind - so that 80 per cent of its ore particles are smaller than 44 microns – Aguia has hit a 50 micron average sweet spot, freeing up more gold.
To ramp up processing and lift gold recoveries, management will swap out its 20HP mill motors for more powerful 40HP units, tweak the agitation circuit and fine-tune its Merrill–Crowe extraction system.
The company is now also adding cyanide earlier into the process - during grinding – which has cut down leach tank time and allows it to potentially boost plant throughput without losing any recovery. It is targeting more than 90 per cent metallurgical recovery now.
Aguia says the various changes are starting to deliver the goods. Doré bars have been produced and shipped to a refinery in Medellin for analysis in a symbolic milestone for the project and a vote of confidence in the new strategy.
With a revamped operational crew, a plant running at higher efficiency and a tantalising new vein system potentially tying the entire goldfield together, Aguia may just be entering a new golden era at Santa Barbara.
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By James Pearson
