Aguia Resources has fired the starting gun on what could be a game-changing drilling campaign at its Santa Barbara gold project in Colombia, after early-stage results hinted at the discovery of a high-grade gold system lurking 40 metres beneath the existing mine.
The ASX-listed explorer has sunk the first two holes of a 25-hole campaign and has already struck mineralised quartz veins and key fault structures. Importantly, the hits appear to confirm its geological model and tease at the potential of a much bigger gold system.
The company’s first drill hole intersected a 4-metre mica zone at surface, containing small quartz veining. The veining was followed by a separate 10-centimetre quartz vein at 6m depth.
Further down the hole, the drill bit struck a 0.7m thick quartz vein at a depth of 107.4m, which lit up with visual sulphide mineralisation, including pyrite, sphalerite and galena. These sulphides are often linked to gold.
Aguia says the deeper intersection appears to be an extension of vein 1, which has already been partially mined in a trial operation that processed 500 tonnes at an average of 20 grams per tonne (g/t) gold.
The hole also cut through a key fault zone at 52m, confirming the structural complexity previously predicted by the company’s geologists.
The second hole, still being drilled to reach 138.6m depth, has struck the same near-surface veining and is showing a similar mineralised system beyond the fault. Together, the two drill holes have covered nearly 300m of drilling so far.
The current drilling program is designed to target vein systems within a 7km-long mineralised corridor. Except for the first few holes, the drilling is planned to test near-surface mineralisation in holes that are shorter than 100m.
Assays are pending. When the results are in, Aguia plans to map out the dip, strike and offset of the known gold-bearing veins for future mine planning and resource modelling.
The gold at Santa Barbara seems to come from a mix of mesothermal and epithermal rocks, with signs of repeated mineral activity. The veins are found in pinkish rock, called San Lucas gneiss, which contain broken rock textures with coarse galena and yellow sphalerite - both are signs of a strong gold system.
The project’s vein system appears to be showing striking similarities to two of Colombia’s biggest gold hitters, the Segovia and Buriticá mines.
When Canadian outfit Continental Gold unveiled its maiden resource at Buriticá in 2011, it stunned the market with 3.1 million ounces of gold and 11 million ounces of silver - all pulled from just 14 veins in the Yaraguá zone.
Some of those veins were razor-thin at just 3cm wide and were often tightly packed within 50m of each other, much like Santa Barbara’s mineralisation.
It was no surprise when the company revealed an internal study in April estimating a jaw-dropping exploration target of two to four million tonnes of material grading up to 30g/t.
Aguia Resources executive chairman Warwick Grigor said: “We have always been confident that we can build on the earlier trial mining and testing program to develop a small but highly profitable underground gold mine. The real speculative appeal comes from the possibility that we could be sitting on a large high-grade gold resource.”
To keep the momentum going and subject to success, Aguia is planning to bring a second drill rig in on the action to expand the program and target deeper extensions of the mineralised zones.
Meanwhile, the past few months have been a hive of activity on site as Aguia busied itself with the restart of gold production.
Underground, the old workings have been fully rehabbed with a fresh ventilation system, upgraded electricals and a slick new electric locomotive now running through the tunnels.
Up top, the processing plant has had a facelift. It’s now turning over 30 tonnes per day of ore, with a bump to 50tpd expected by July when a new primary crusher comes online.
Perhaps the biggest win came six weeks ago, when Aguia cleared a key regulatory hurdle, locking in full government approval to sell its gold locally and internationally. With the green light in hand, the company has wasted no time cashing in - just as gold prices flirt with record highs of more than $5000 an ounce.
With assays pending and the drills turning, Aguia is positioning itself for what could be a major gold discovery in the making. If grades come back as hoped, Santa Barbara might just turn from a speculative play into Colombia’s newest underground gold story.
Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au
By James Pearson
