Altar is defined by three distinct deposits: Altar Central, Altar East and QDM Gold.
Altar Central and Altar East are constrained using a single openpit and therefore are reported together. Altar Central and Altar East are separated into supergene copper (secondary sulphide) and hypogene copper-gold (primary sulphide) mineralisation.
Altar Central and Altar East host a measured and indicated resource of 1.2 billion tonnes grading 0.43% copper, 0.09 grams per tonne gold and 1g/t silver, and an inferred resource of 189.2 million tonnes grading 0.42% copper, 0.06g/t gold and 0.80 g/t silver at a 0.30% copper-equivalent cut-off. This resulted in a 41% decrease in tonnage and a 29% increase in copper grade for measured and indicated resources and a 66% decrease in tonnage and a 48% increase in copper grade for inferred resources compared to the 2018 estimate.
The new estimate also reduced the arsenic in measured and indicated resources by 39% and in inferred resources by 67%. The separation of the supergene and hypogene mineralisation showed that a high percentage of arsenic is located within the supergene portion of the deposit, which can potentially be processed using SX/EW technology where arsenic is not recovered.
The QDM gold deposit hosts a measured and indicated resource of 20Mt grading 0.78g/t gold, 3.62g/t silver and 0.06% copper and an inferred resource of 1.2Mt grading 0.58g/t gold, 5.34g/t silver and 0.03% copper. About 90% is sulphide mineralisation and 10% oxide mineralisation.
"By utilising a higher cut-off, we have been able to show the better grade portions of the deposits. The result is a higher-grade, reduced tonnage estimate that we feel is a much more attractive alternative," said Aldebaran Resources CEO John Black.
"With the resource now re-cast, our focus turns to further exploration to test the many targets identified on the project. Our primary goal is to find additional higher-grade mineralisation that could further improve the overall grade profile of the project."
Additional potential exists at three additional porphyry centres: Radio porphyry, QDM porphyry and Altar North, which were not included in this estimate due to insufficient drilling. Current drilling is targeting extensions of known higher-grade mineralisation.
Aldebaran has the right to earn up to an 80% interest in the Altar project.
Share in Aldebaran Resources are trading at C50c, valuing the company at $47 million.