At least five extensive ionic adsorption clay (IAC) rare earths deposits have been identified at Mount Ridley’s namesake project in WA.

IAC deposits – like the ones exploited in southern China — are commonly considered to be some of the cheapest and most readily accessible sources of heavy rare earths.

They are also hard to come by ex-China, with only a handful of these IAC projects on the ASX.

Mount Ridley Mines (ASX:MRD) says the identification of relatively shallow REE accumulations over an apparent strike more than 25km was the result of a critical re-examination of data generated during nickel drilling campaigns over the previous five years.

Re-assaying of 950 air core samples – with 162 pending — returned significant REE values over an apparent strike of more than 25km.

Based on the clusters of existing drill holes with REE results available, the project has been grouped into five exploration prospects.

They are Winston’s (2.6km long and 1km wide), the Lake (3km by 1.6km), Keith’s (2km by 1km), Tyrrell’s and Marcellus.

Mount Ridley

More than 20 samples returned impressive values over >1,000 ppm TREO.

Mineralisation remains open in all directions with a peak value so far at the ‘Keith’s’ prospect with 10,461ppm (1.05%) from 23m downhole.

Early results compare favourably to Ionic Rare Earths’ (ASX:IXR) Makuutu resource in Uganda, says Mount Ridley.

Upcoming work programs

Mount Ridley recently expanded its REE-prospective ground position to 3,400sqkm.

Planning is now underway for a 25,000m aircore program to test newly acquired tenements, in addition to step-out and infill holes.

Reverse circulation drilling will be used for the Mineral Resource drill-out, and diamond or sonic drilling will be used to provide in-tact regolith for geotechnical and metallurgical testing, the company says.

“Heritage, flora, and fauna surveys will be updated over the coming months as required, focusing on the identified target areas and extensions to known REE mineralisation,” it says.

“Early-stage mineralogy and metallurgical test work will be carried out using material generated from the upcoming drilling.

“This is considered critical in determining the nature and extractability of the REE mineralisation.”



This article was developed in collaboration with Mount Ridley, 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.