Sunstone starts drilling at large T2 copper-gold porphyry target

Sunstone could soon have greater insight into the true scale of the T2 porphyry target within its El Palmar project with the start of drilling to test the geophysical anomaly.

Already, the first hole EPDD026 at T2 has reached a depth of 300m and identified trace chalcopyrite and molybdenite from 190m downhole with the target zone expected to be reached within a fortnight.

This follows drilling intersecting copper and gold at the T1 and T5 porphyry targets adjacent to T2 and an epithermal gold-silver system at the Tituana target.

Sunstone Metals (ASX:STM) notes that drilling at T5 intersected porphyry mineralisation including 60m grading 0.25 grams per tonne (g/t) gold and 0.13% copper from 100m its while 3D geological model has defined new targets at T1 after drilling returned a 867m intersection at 0.26g/t gold and 0.1% copper from surface (EPDD021).

It considers the results from T1 and T5 to be promising as they are close to the large T2 target and support the current interpretation of the El Palmar geology and the potential for a significant porphyry discovery.

They also reinforce the concept of a cluster of porphyry systems near the regionally significant Toachi fault, a control on the mineralisation at the giant Cascabel copper-gold deposit 65km away.

Additionally, dating of the intrusives associated with the El Palmar mineralisation show they are the same age as the Alpala deposit at Cascabel.

Running two rigs

“We have two drilling rigs operating at El Palmar. One is testing the Tituana epithermal target where we have intersected very encouraging mineralisation across multiple vein systems, and the other has commenced drilling at the large T2 porphyry copper-gold target where we are seeing some trace levels of mineralisation and encouraging alteration,” managing director Malcolm Norris said.

“We expect to be in the main T2 target zone within a fortnight.

“At Tituana, assays have been received from the first three holes of an 11-hole program. The results confirm the presence of an epithermal gold-silver-base metal system in multiple veins.

“Visual results from recently completed holes suggests that mineralisation extends over 200m of strike but is open to the north and south.”

T2 drilling

T2 has been defined at surface through rock chip and soil sampling delivering a coherent gold-copper-molybdenum anomaly coincident with an extensive alteration cap and some stockwork veining.

Sunstone’s first of two planned holes is testing a geophysical anomaly that plunges to the south from the surface mineralisation, where it expands and intensifies southward for a further 800m.

Drilling has already demonstrated evidence of mineralisation in the upper part of the hole that is consistent with results from the adjacent hole EPDD024 and is expected to be completed in late March, with assays following in late April.

Tituana drilling

Over at the Tituana epithermal gold target, drilling has intersected an epithermal system with mineralisation in multiple veins.

Visual assessment of holes 6 and 7 suggest improving mineralisation to the north based on the presence of galena and sphalerite which are often associated with gold and silver in these epithermal systems.

Tituana is located on a north-northeast trending structure that may link to the south to the main El Palmar porphyry system – a common scenario in porphyry and epithermal systems.

It exhibits coincident path-finder elements zinc and arsenic anomalies in soil sampling.

This article was developed in collaboration with Sunstone Metals (ASX:STM), 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.