Nexus Minerals Limited, an ASX-listed exploration company, has identified an opportunity to access under-explored landholdings in Victoria and New South Wales, both of which are highly prospective for critical minerals.
The 12-month assessment and evaluation study resulted in the company’s emerging ground position of critical mineral exploration projects in Australia. The critical mineral search commenced by assessing the LCT pegmatite potential of the Lachlan Orogen of Victoria and New South Wales. This extended to the association of tin mineralisation to the emplacement of LCT pegmatites.
New South Wales findings
Over 15,000km2 of prospective critical minerals ground tenure was granted, with first mover advantage allowing for regional scale exploration targeting with one of the largest pegging exercises in New South Wales history.
Nexus reviewed geology and lithogeochemical data from the Wagga-Omeo Zone (WOZ) in southern New South Wales as part of a regional-scale approach to select exploration ground for LCT pegmatites in the Lachlan Orogen. The objective was to establish from first principles intrusive rocks permissive for LCT pegmatite development and assess their fertility using open-file data rather than focusing only on known tin and lithium occurrences.
A review of open file geology and whole-rock geochemistry confirmed that much of the exploration ground applied for in southern New South Wales is underlain by reduced, fractionated, peraluminous S-type granites similar to those associated with the spodumene-bearing pegmatites of the Dorchap Range in north-eastern Victoria.
The tenure is considered prospective for lithium, cesium, tantalum and tin, with Nexus having a first mover advantage in the region, allowing for regional scale exploration and targeting.
Findings in Victoria
Fieldwork commenced on the existing Nexus Granya LCT pegmatite project. The Granya project was acquired in April 2021 as part of the Bethanga porphyry Cu-Au acquisition.
Nexus also signed an option deal for the Merrimac LCT pegmatite project, with a range of terms and conditions that have been agreed upon.
Nexus also has five LCT pegmatite prospective tenements under application.
The company has also entered into an option agreement to explore and acquire the Merrimac Project (Merrimac) in north-eastern Victoria. The project hosts known LCT pegmatites and tin mineralisation and abuts one of Nexus’ under-application tenements that also hosts known LCT pegmatites and tin mineralisation.
In addition to the positive results from the Bethanga porphyry Cu-Au fertility assessment study, this extensive new ground position over a hugely underexplored and prospective region, will allow Nexus to undertake the search for critical minerals in a significant manner.
The discovery of spodumene-bearing pegmatite dykes in the Dorchap Range of north-eastern Victoria has spurred exploration interest for critical minerals in this region and further north into New South Wales.
Lithium-cesiumtantalum (LCT) pegmatites appear to be associated with highly fractionated, reduced S-type Silurian granites that also often host tin mineralisation. The LCT pegmatites of the Dorchap Range are associated with the historical primary tin fields at Mitta Mitta and Mount Wills.
Typically, LCT bearing pegmatites are found approximately three to six km from the contact of a fertile granite intrusion.
Nexus Managing Director, Andy Tudor, said that while Nexus Minerals is focused on the Wallbrook project in the Eastern Goldfields of Western Australia, it has also been a very productive 12 months of work that has led the company to establish a significant ground position, in such a prospective region.
“The results from our desktop review and the opportunities identified have led us to undertake one of the largest pegging exercises of ground in New South Wales. Field crews are already on the ground across multiple project areas commencing initial ground truthing,” Mr Tudor said.
“This critical mineral search will be undertaken alongside the exploration planned for the company’s Bethanga porphyry Cu-Au project”.
