Sunstone Metals Ltd (ASX:STM) has intersected more broad zones of gold-copper mineralisation, including sub-zones of higher grades, at Bramaderos Gold-Copper Project in southern Ecuador, which will underpin the upcoming initial mineral resource estimate (MRE) for the Brama-Alba porphyry discovery.
Resource drilling at Brama and Alba has been completed but mineralisation is open in several areas beyond the planned resource boundary.
The company will provide an exploration target to increase the resource base of Brama-Alba in 2023 when it publishes the MRE, currently targeted for December.
Wide zones
Assays received from six drill holes at Alba and four holes from the eastern end of the Brama system include:
- 49.45 metres at 0.60 g/t gold-equivalent (0.37 g/t gold and 0.13% copper) from 392 metres;
- 32 metres at 1.20 g/t gold-equivalent (0.87 g/t gold and 0.20% copper) from 386 metres;
- 115 metres at 0.66 g/t gold-equivalent (0.41 g/t gold and 0.15% copper) from 12 metres, including 24.15 metres at 1.10 g/t gold-equivalent (0.46 g/t gold and 0.38% copper) from 31.35 metres; and
- 69 metres at 0.61 g/t gold-equivalent (0.36 g/t gold and 0.14% copper) from 21 metres.
Plan showing the status of drilling at Brama-Alba on a backdrop of gold-in-soil results. Latest drill holes are highlighted in yellow.
More evidence
Sunstone managing director Malcolm Norris said: “These results are more evidence of the substantial widths of mineralisation which will form part of the initial MRE.
“The MRE, which we expect to deliver in December, will be the first step to building a significant inventory of gold and copper at Bramaderos.
“In addition, the drilling of new targets to deliver further discoveries with the potential to significantly increase the resource base is now underway with encouraging initial results.
“We have a lot to deliver at Bramaderos during the remainder of 2022.”
Good infrastructure
The Bramaderos Project is immediately adjacent to the Pan American highway and is close to available hydroelectric power, which will support future development opportunities.
The project is also supported by nearby commercial airports and significant cities such as Loja, with a population of 200,000, and has strong community support.
Other activities
Sunstone has also resumed discovery drilling at the Melonal, Sandia and Limon porphyry targets within the Bramaderos concession.
Logging of the Sandia and Melonal holes returned visible copper mineralisation consistent with Brama porphyry-type systems, while drilling at Limon has yet to reach target depth.
At El Palmar, the explorer reports that drilling is in progress on target T2 while several additional drill targets have also been defined. These will be tested over the coming months.