Drilling strikes new copper-gold porphyry at Sunstone’s Bramaderos project

Sunstone’s drilling has uncovered a porphyry gold-copper system at the Limon target that has the potential to substantially upgrade the scale of its Bramaderos project in southern Ecuador.

Drilling at the 1.5km by 1km target returned a top hit of 79m grading 0.9 grams per tonne (g/t) gold equivalent (0.52g/t gold, 0.19% copper and 9.4g/t silver) from a down-hole depth of 90m which included a higher grade 34.7m intersection at 1.26g/t gold equivalent from 94m (LMDD010).

The drill results are down plunge from a surface trench which delivered 97.6m at 1.08g/t gold equivalent.

What’s of especial interest to Sunstone Metals (ASX:STM) is that the new porphyry find is located 2.7km northeast of the Brama-Alba porphyry gold-copper resource of 156Mt at 0.53g/t gold equivalent, or 2.7Moz contained gold equivalent, and reinforces the concept that multiple old-copper porphyry systems are present within Bramaderos.

Further drilling at Limon is expected to allow the company to convert part of its current Exploration Target of between 255Mt and 360Mt at 0.4g/t to 0.74g/t gold equivalent into resources. Exploration drilling is currently ongoing at the target.

“The Limon discovery could have a potentially substantial impact on the total resource, the overall grade and the upfront development options at Bramaderos,” managing director Malcolm Norris said.

“These results are very exciting because they deliver ore-grade porphyry mineralisation in drilling that extends from surface over substantial widths.

“The shallow and relatively higher grades allow us to contemplate development options that may include higher grade starter pits.”

Limon adding size and grade

The discovery at Limon is significant due to the size of the target and the higher grade of mineralisation intersected over significant widths thus far.

That this extends from surface and remains open just makes the discovery all that much sweeter for the company.

Drilling is currently underway on the high sulphidation targets located in the northeast portion of Limon where previous drilling returned results such as 15.4m at 0.1g/t gold, 0.42% copper and 2.3g/t silver from 57.8m.

Planning is also underway for a follow-up to LMDD010 with modelling of magnetics indicating a 300m plunge to a 100m by 100m magnetic body that is likely related to the porphyry mineralisation.

Additionally, this body is connected to a larger magnetic feature at depth.

Work is also being carried out for deeper drilling based on geological interpretations of a significant porphyry target, and as follow up to previous drilling,

This article was developed in collaboration with Sunstone Metals, a Stockhead advertiser at the time of publishing.

This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.