- Gravity surveying at the Destiny project over magnetic features defines new high priority targets
- Targets have potential to host niobium, REE or nickel-copper-PGE mineralisation
- Grid-spaced survey over three targets to be carried out before drilling
Special Report: Gravity surveying at St George Mining’s Destiny project in WA’s Eastern Goldfields region has defined new high priority targets with the potential to host niobium, rare earths or nickel-copper-PGE mineralisation.
Destiny covers 3,350km2 of ground in the Coolgardie mineral field over 110km of the Ida Fault, a major crustal-bounding structure that is considered to be highly prospective for REE and lithium mineralisation.
A detailed magnetic survey flown by St George Mining (ASX:SGQ) in late 2023 identified four prominent magnetic features, which along with two existing magnetic features, are interpreted as late stage intrusions.
Drilling along strike to the south of the intrusions has already confirmed clay-hosted high-grade REE mineralisation associated with the Ida Fault and across a strike of more than 10km with the mineralisation open in all directions.
Gravity backs potential for carbonatites, late stage intrusions
The gravity survey confirms that four of the six magnetic features have a high gravity signature, raising the exciting potential for them to be intrusions such as carbonatites or mafic intrusions that are known to host either niobium, REE or nickel-copper-PGE mineralisation.
This interpretation is supported by the proximity of the features to the Ida Fault.
Importantly for SGQ, at least two of the features have characteristics similar to known mineralised carbonatites in WA such as Lynas Rare Earth’s Mt Weld project and WA1 Resources’ Luni carbonatite, which present as distinctive geophysical features along major crustal structures.
“As part of the systematic exploration of the Destiny project, a gravity survey was recently completed to assess the density characteristics of six discrete magnetic features – none of which has been drilled,” executive chairman John Prineas said.
“The survey indicated that four of the six magnetic features presented as ‘gravity highs’ – a combination that is common for mafic intrusions and carbonatites. Significantly, these features are within a major structural corridor close to the Ida Fault – a major crustal suture zone.
“This combination of high gravity signatures, magnetic geometry and geological setting at Destiny warrants further investigation to determine the potential for any mineralisation to be associated with these distinctive geophysical features.
“These targets are relatively easy to explore and we consider they have potential for high-grade discoveries, such as Nb-REE mineralisation or Ni-Cu-PGEs.
“Drilling has been prioritised to test these new targets and we look forward to providing exploration updates as we advance this promising development.”
Targets outlined
The targets outlined by the company’s work to date include Target C1, a circular shaped feature with a distinctive magnetic rim and gravity high core.
It abuts the Ida Fault and has a 2.1km diameter with an interpreted ultramafic rim. Given the size of the feature, follow-up grid spaced gravity to further refine the target is warranted with drilling planned to test the rim and core of the feature.
Target C2 has a near-circular magnetic rim, but is a gravity low core suggesting a lower priority target while Target C3 is a large magnetic low with a gravity high core. No magnetic rim is apparent, however, there are magnetic features within the body that warrant investigation.
Importantly, C3 is along a major splay off the Ida Fault that may have acted as its conduit to emplacement. A follow-up gravity survey to further refine a target is warranted with drilling to follow.
Target C4 is an elliptical intensive magnetic anomaly, however, the gravity to date has shown variable results. A closer spaced gravity survey is planned to better delineate this target.
Targets C5/C6 both returned coincident magnetic and gravity high values. They are isolated strong magnetic anomalies that can be tested by drilling with no further gravity survey required.
Next steps
SGQ will carry out a grid-spaced gravity survey over the C1, C3 and C4 targets.
This will be followed by drilling – likely in 2H 2024 – once the gravity data is assessed.
This article was developed in collaboration with St George Mining, 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.