Comparison of results from aircore drilling at the Whaleshark copper-gold Project in WA’s Ashburton region with results from research at Prominent Hill indicate the potential for the REE anomalism to be related to buried IOCG mineralisation.

While Miramar (ASX:M2R) has been exploring at Whaleshark since listing back in October 2020, researchers in South Australia only recently examined the REE content of monazite grains within and above Oz Minerals (ASX:OZL) Prominent Hill and Carrapateena IOCG deposits.

Monazite is a hard and relatively dense phosphate mineral that contains significant levels of REE’s such as lanthanum (La), cerium (Ce), neodymium (Nd), samarium (Sm) and praseodymium (Pr).

IOCG deposits commonly contain anomalous REE’s – at Prominent Hill and Carrapateena, the researchers showed that the REE’s within the primary IOCG mineralisation mostly occur within monazite grains.

Back in November, samples from an initial drilling campaign at Whaleshark were analysed for a multi-element suite and using the same criteria as Prominent Hill, results showed several interesting and compelling REE results pointing to a primary IOCG source.

What did the results show?

Hole WSAC055 has several samples which returned high lanthanum and cerium with corresponding low yttrium and thorium, which come from a strongly weathered and medium grained granitic unit.

This hole is located within the largest of the three mobile metal ions (MMI) soil anomalies and an interpreted WNW-trending structure crosscutting the granite intrusion which has been poorly tested to date.

Gravity data also shows the WNW structure and an area of subtle gravity anomalism.

All the right ingredients: scale, magnitude, and suite of elements

“The first pass interface aircore drilling at Whaleshark outlined multi-element anomalies in several elements generally associated with IOCG mineralisation, including copper and rare earths,” M2R executive chairman Allan Kelly says.

“The scale, magnitude and suite of several elements seen at Whaleshark is similar to the large Ernest Henry IOCG deposit in Queensland and the comparison of the rare earth element data with Prominent Hill is equally as encouraging.

“We are looking forward to getting back to Whaleshark next year and continuing to uncover the potential of this exciting project.”

Next on the agenda

The plan for next year is to complete heritage surveys over all potential drill targets, carry out ground EM surveys over the large MMI soil anomalies and conduct bedrock diamond drilling or interface aircore drilling – depending on the results.




This article was developed in collaboration with Miramar Resources, 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.