Southern Hemisphere Mining says drilling at its Chilean copper-gold project has closed the mineralisation links between its adjoining Cerro and Ferro zones, with assay results from the recent program showing up to 76m at 0.44 per cent copper equivalent.
Management says the latest results have significantly advanced its Llahuin project, with all drilling targets intercepting mineralisation. The program had been aimed at amalgamating the company’s adjacent prospects that lie within a big geochemical halo into a single, large resource, in addition to improving on historical grades.
Management says the work also confirmed the potential for a feeder zone or rootstock at Cerro and Ferro, which will require more drilling for further development.
Additionally, the program’s highlight 76m hit at Cerro also bored through a useful 14m at 0.79 per cent copper equivalent from surface, with 48m in a second hole going 0.45 per cent from surface south-east of the Ferro deposit – thereby extending the overall scale of the Cerro-Ferro zone. A further two separate holes at Cerro jagged 12m at 0.66 per cent copper equivalent and 14m at 0.54 per cent, both also from surface.
Broad porphyry-style mineralisation up to 164m at 0.16 per cent copper equivalent and 106m at 0.13 per cent was also intersected in two holes at the large greenfields Southern target.
Southern Hemisphere believes the higher grades at Cerro than had been obtained in previous drilling could be due to a change in drilling direction and possibly because previous holes were wet, which may have introduced some sample bias.
With the geochemical footprint of the Cerro-Ferro link target being about 600m long north-south by 400m wide east-west, the new information demonstrates that the two target areas comprise a single mineralised system, stretching at least 1.9km of its north/north-easterly strike distance.
Management believes there is now the potential to increase the overall near-surface mineral resource by combining Cerro and Ferro as almost all of the results to date are relatively shallow, less than 200m below surface, and many run from at or near the surface.
At Ferro, three holes were put in to test the “Ferrocarril Fault Zone” considered to be another high-priority target area for future drilling. Two holes intersected the mineralised fault zone and ended in mineralisation.
One hole hit 44.3m at 0.29 per cent copper equivalent, ending in mineralisation at the 272.3m termination depth after passing through the fault. A second hole drilled towards, but outside the fault still jagged 48m from surface at grade of 0.45 per cent copper equivalent.
But most spectacularly, a third hole ran 219m from surface, with mineralisation averaging 0.24 per cent copper equivalent.
The results come after Southern Hemisphere had previously outlined a 2500m program of diamond and reverse-circulation (RC) work at its 149-million-tonne Llahuin porphyry copper-gold project, 250km north of the Chilean capital of Santiago.
Ongoing work will include completing geological mapping between the Southern porphyry zone to Cerro along a strike distance of about 3.7km. As part of the mapping work, it will also employ 3D deposit alteration mapping of the core using Terraspec.
Samples have already been sent for analysis to provide low detection limit data for 3D “deposit footprint” modelling work.
The drilling program has achieved a lot and provided management with greater confidence of the mineralisation and its potential. It could be said that the original objectives of the program have been achieved and even surpassed and have thrown up new targets and new potential resources or extensions to the existing estimated resource that comprises 680,000 tonnes of copper equivalent.
Is your ASX-listed company doing something interesting? Contact: office@bullsnbears.com.au