In preparation for our annual report, we interviewed our Head of Geology, Ross Armstrong, who shared the latest developments and insights from the geology team.
Please tell us about the latest exploration findings at Viscaria.
It’s been hugely exciting to embark on this exploration campaign. Drilling in the B and D zones has proven the continuation of the copper mineralisation down to 1.2 kilometres, far deeper than the current modelled resources are defined. On top of this, we discovered a new copper-rich horizon, which is positioned at depth between the A and B zones, just a few hundred metres from the existing underground infrastructure. These results have outlined a significant growth potential for the Viscaria deposit that we are continuing to assess and quantify with the ongoing drilling programme.
How accurately can you predict the geological conditions at depth based on the data you have?
There is always an inherent risk in exploration. There are no guarantees for the metres you drill. But there are of course various ways in which we can apply our knowledge to increase the chance of discovery. Our geological interpretations have been complimented along the way with detailed structural and geophysical analysis. In particular, the modelling of geophysical anomalies has proven incredibly successful throughout this exploration campaign, consistently predicting the position of the mineralisation and accurately guiding the drill hole planning.
What are the most important steps in the exploration strategy going forward?
So far, we have had powerful momentum in a very natural way as the drill holes have yielded promising results. VIscaria’s deep roots remain open, with the geophysical data indicating that the mineralisation extends beyond the areas that we have managed to drill so far. It is important for us to test and assess this wider exploration potential, so that we can learn more about the Viscaria deposit and the true size of the ‘beast’. First and foremost, however, the immediate plan is to prove continuity in the geology and grade between our drilled intersections, which will allow us to estimate additional resources from our existing zones and, for the first time, from the ABBA zone. Ultimately, we want to turn these exciting drilling results into impactful tons that can be incorporated into the future mine plan.
How do you ensure that the new discoveries contribute to an increase in the mineral resource?
The key here is to prove that your drilled intersections are not anomalous or heterogeneous, but rather that there is good correlation in the geological observations between each of the drill holes. This helps to build confidence in the concept that the initial results are representative of a continuous body of mineralisation that has reasonable prospects for eventual economic extraction. In this regard, the early signs look extremely promising for us, and we have maintained tight dialogue with the Competent Person to ensure that our drill hole spacing will be satisfactory in defining initial resources at the inferred level.
Working on the Viscaria deposit has always been exciting, but the latest results have taken that feeling to the next level.
What do the latest findings mean for the future development of the project?
It’s quite early to say just how big the impact will be, but certainly the initial findings have proven the existence of thicker and higher-grade mineralisation beneath the current resources, and so this would point towards a longer-term underground mining operation than what has been previously considered. It’s simple to imagine that as you build a mine deeper, you need to find more-valuable resources in order to justify the higher extraction costs and still make a profit. The indications from these exploration results would suggest that this is a distinct possibility and that we have a clear opportunity to extend the initial Life of Mine plan in the future.
Have the new findings changed your view of Viscaria?
It has always felt exciting to be working on the Viscaria deposit, but these latest results have taken that feeling to the next level. The potential here is huge – not only at depth beneath the existing zones, but also in the significant exploration spaces that exist at other positions within the wider stratigraphic package, highlighted by the discovery of the ABBA zone. These findings have outlined a high-grading direction for the deposit, which could grow rapidly over the coming years with further successful exploration.
Are there any plans to expand exploration into new areas?
Our focus over the past years has been on securing a profitable and predictable re-opening of the Viscaria mine. As we near the completion of our Feasibility Study, we want to turn a part of that focus back towards the surrounding region, across which we have already consolidated a significant package of exploration permits. This is part of our ‘Grand Viscaria’ vision, which incorporates both near-mine and greenfield exploration, with commitment to making real copper discoveries that can feed the processing plant in Viscaria for many, many years to come. We already have plans this spring to drill in our permit areas outside of the mine site, so hopefully we will be able to share some more exciting news from there in the near future.