Perth-based explorer Tesoro Resources (ASX: TSO) has identified a significant zone of gold mineralisation following drilling at the Ternera East deposit within the El Zorro project in Chile.
Assays from two holes have returned positive gold intercepts in the hanging wall zone of Ternera, providing potential to enhance the economics of any future open pit mining operation through a reduced stripping ratio.
Best results were 37m at 0.49 grams per tonne gold from 297m, including 7.5m at 1.15g/t from 298.5m; 1m at 3.68g/t from 305m; and 3.5m at 1.54g/t from 329m.
Assays remain outstanding for another 48 holes.
Favourable host rock
One of the holes intercepted multiple altered bodies of the El Zorro Tonalite (EZT) which is the project’s favourable gold host rock.
Zones of strong alteration and associated gold mineralisation were defined where the EZT has been fractured by primary north-south faults.
These zones are believed to be consistent with the El Zorro mineralisation model and provide geological confidence that gold mineralisation is likely to occur in the region.
The results confirm that previously-identified outcropping intrusive bodies 400m to the east of Ternera host significant gold mineralisation from surface to depth.
Managing director Zeff Reeves said the discovery demonstrates the deposit’s potential to host additional gold resources outside of the greater Ternera mineral resource estimate area.
“We believe Ternera is part of a large intrusive-related gold system analogous to Alaska’s Tintina province and that repetitions within the district are possible as shown by these early [drilling] results,” he said.
“We now have two rigs focused on delineating a gold resource at Ternera East which should evolve very rapidly.”
Good news flow
This is not the first good news story to come from drilling at Ternera East.
Last month, Tesoro reported the first hole drilled at the deposit hit gold in two zones of the EZT.
That exercise returned results of 21.28m at 0.34g/t gold from a depth of 97.5m, including 4.5m at 1.14g/t from 105m; and 36m at 0.4g/t from 243m, including 4m at 1.69g/t from 249m and 1.05m at 1.77g/t from 273m.
And in June, the company posted high-grade results from extensional and infill drilling at Ternera which extended the mineralisation to the east by 150m.