Estrella hits further nickel-copper sulphides at Carr Boyd project

Estrella Resources Limited (ASX: ESR) announced that a further significant drill intersection of Ni-Cu (+ PGE) bearing sulphides was intersected in diamond core hole CBDD033 at the T5 discovery zone within the Company’s flagship Carr Boyd Project.

The company reported that a 25.7m wide zone of nickel-copper (Ni-Cu) sulphide mineralisation was intersected in hole CBDD033 which drilled through the Carr Boyd Layered Complex ~25m north of the discovery hole CBDD030 at T5.

ESR noted that the mineralisation is hosted within a gabbroic host unit intruded along the contact zone of the CBLC and comprises pulses of Ni-Cu bearing massive, matrix, disseminated, and breccia sulphides.

The company reported that the intersection is consistent with the EM conductor plate and validating the geophysical modelling to date.

ESR reported that two diamond core rigs are now drilling 40m apart on the T5 discovery zone in order to expand on the mineralisation currently being defined at the T5 zone.

Carr Boyd project

The Carr Boyd Nickel Project is located in the north of Kalgoorlie in Western Australia and is a major focus for Estrella Resources Limited.

The Carr Boyd Nickel Project covers the Carr Boyd Layered Complex (CLBC), a 75sq km mafic igneous complex that hosts several nickel and copper sulphide occurrences – the most significant being the Carr Boyd Rocks mine.

The Carr Boyd Rocks nickel mine was the first magmatic hosted style of nickel deposit discovered and mined in WA. The mine was discovered in the late 1960’s and produced 202,110t of ore at an average grade of 1.43% Ni and 0.46% Cu between 1973-1977.

T5 prospect within the Carr Boyd Nickel Project is located 1.1 kilometres northeast of the historic Carr Boyd mine and was identified in 2019 after reverse circulation (RC) drilling.

Estrella Resources’ recent reverse circulation (RC) drilling into the T5 target had intersected 11m of mineralised basal contact zone, including 5m of strong matrix-style nickel and copper sulphides. After this recent discovery, the company was planning for future drilling in the area.

In October 2020, ESR made a massive nickel sulphide discovery within the Carr Boyd Project. The sulphide mineralisation was 2.9 metres thick and was intersected at the southern end of the T5 prospect.

Drilling at T5 target

The original discovery hole CBDD030 was drilled from the footwall sediment side in order to provide a deep EM platform hole to test the basal contact position for sulphide accumulations.

Estrella said that diamond core hole CBDD033 was drilled from the opposite direction, drilling back through the CBLC mafic-ultramafic intrusion towards the contact zone targeting above the discovery intersection.

ESR reported that the discovery hole CBDD030 intersected the CLBC contact, was completely blind, and is open in all directions

Important results included 2.5m @ 3.66% Ni, 0.46% Cu, 0.16% Co, 2.09g/t Ag & 0.78g/t Au+Pt+Pd, with 2.98% MgO; within a zone grading 3.7m @ 2.85% Ni, 0.65% Cu, 0.13% Co, 2.58g/t Ag & 0.75g/t Au+Pt+Pd, with 5.65% MgO; and overall grade of sulphide zone grades 13.9m @ 1.07% Ni, 0.39% Cu, 0.05% Co, 1.56g/t Ag & 0.48g/t Au+Pt+Pd, with 10.84% MgO.

Significant magmatic Ni-Cu mineralisation

The company reported said the hole CBDD030 intersected more Ni-Cu sulphides along the contact zone and is associated with coarse grained gabbroic rocks intruded up the contact between the serpentinised ultramafics of the CBLC and the footwall basalts.

ESR said that the sulphide mineralisation occurs over a substantial 25.7m downhole wide zone (~20m true width) comprising of pulses of Ni-Cu bearing massive, matrix, disseminated, and breccia sulphides.

ESR said that additional stringers and blebby sulphides occur within the footwall basalts outside of the reported zone, supporting the intrusive remobilised nature of these sulphides being derived from a larger primary sulphide source chamber at depth.

Updates and next steps

The company reported that two diamond core rigs are currently onsite drilling 40m apart at the T5 Discovery Zone as the company’s geological team map out the extend of the sulphide zone as well as planning the next stages of stepping out and exploring the deeper primary source of these remobilised nickel-copper sulphide discovered to date.

ESR said that a DHTEM crew is currently on site surveying the completed holes and the results of the survey will assist the geological team to modify the drill hole targeting for the next round of drill holes.

The company said that continued deep diamond drilling is underway and DHTEM geophysical testing of the drill holes will commence soon.

Management statements

Estrella Resources MD and CEO Chris Daws said: “Our team has again delivered another significant drill hole confirming the extensive DHTEM plate surrounding our initial discovery hole hosts substantial nickel sulphide mineralisation. We are moving fast to see what further mineralisation exists at T5 with two diamond rigs drilling 24/7 into the defined DHTEM plate, I expect from here we will continue to see more significant results. I am extremely pleased with what has thus far been achieved and I look forward in the days, weeks ahead as the drill bits keep turning on what has been a remarkable program to date.

As the Company gears up for expanded drilling efforts focusing on the T5 Target area we are also rapidly expanding our infrastructure at the project location. We have recently improved the communications at site, with the erection of a communications tower to provide high speed internet and reliable phone service. The old haul road is now being graded and improved to facilitate the transport of an exploration camp and office block buildings to site,

The core yard facility upgrades, and site office installations are in progress, with bulk water and diesel fuel storage also being established. An old airstrip located 4km east of the Carr Boyd Mine has also been re-established by the local station owner for RFDS and charter flight site visits of Company personnel.”

Written By Jonathan Norris
Jonathan is a founder of and has been covering the resources industry since 2018. With over 17 years experience in print, broadcast and online media, Jonathan has seen first hand the transformative effect of online niche media.