Assay results from five recent deep exploratory drill holes at Intrepid Mines' Tujuh Bukit project have intercepted additional gold and copper mineralization adjacent to and south of the main Tumpangpitu porphyry inferred resource area.
Together, the five diamond drill holes confirm the clear potential for expansion of this first porphyry area of the 11,621 hectare project.
One hole was drilled in the southwest portion of the main Tumpangpitu porphyry, testing a zone outside the current inferred estimate. The hole intersected 604.5 metres @ 0.34% copper and 0.34 grams/tonne gold, including some higher grade zones. The hole finished in mineralization at a depth of 1072.5 metres.
Because this hole intersected mineralization in, and below, the domain of 'exploration potential' as predicted in the resource block model, it is expected to add significant tonnage to future resource estimates, and provides further confidence that previously estimated exploration potential marginal to the inferred resource domains can be converted into inferred resource. It also provides confidence that exploration of still deeper levels will deliver additional mineralization.
Two holes were drilled into a magnetic low embayment between the main porphyry zone and a southern porphyry drilled by a previous hole. These holes confirmed that the magnetic low relates to a diatreme breccia body which postdates most of the mineralization episodes and is therefore only weakly mineralized.
However, this diatreme breccia has been identified in other drill holes and its geometry is now being defined with some confidence. All three holes in this area were abandoned due to poor ground conditions and inability to drill deeper.
Whilst this drilling has failed to follow up on the very encouraging intercept in the previous hole the area remains to be explored with another hole scheduled.
Intrepid's executive general manager, exploration and new business Malcolm Norris says, “Overall, these results are encouraging as we build our geological model of this very large porphyry system.
“Integration with 3D magnetic modelling is proving critical to our understanding of the geometry of target areas. We have five rigs now drilling in areas outside the existing porphyry inferred resource and we are confident of defining significant upside. These rigs are currently at hole depths of up to 450 metres and we look forward seeing how they add to our understanding.”