• First assays from Phase 1 drilling at Sandy Mitchell have validated Ark Mines’ development strategy
  • Results have returned a maximum grade of 3,500ppm for TREO, yttrium and scandium
  • These results will help to delineate a maiden resource later this year


Special Report: Assays from the first phase of drilling carried out on Ark Mines’ Sandy Mitchell project has produced consistent rare earth element (REE) and heavy mineral intersections, building further confidence around its commercial development potential.

Ark Mines’ (ASX:AHK) Sandy Mitchell project, about 300km west of Cairns in Northern Queensland, is unlike few other rare earth deposits on the ASX.

It is hosted in fine sands known as terrestrial placer deposits, meaning a quicker production runway, simpler processing model and lower costs.

AHK has been focused on resource drilling over two stages – Stage 1 comprising 1,488.3m across 144 aircore holes and Stage 2 encompassing 2,425.8m throughout 187 aircore holes.

Reflecting the potential scale of the project, Stage 1 drilling to-date also covers an area of only 1.3 km2 – representing just 1.2% of the peak radiometric reading on the lease which covers 147km2.


Ark Mines asx AHK
Sandy Mitchell rare earth and heavy mineral project location. Pic via AHK


Results supports upcoming resource  

About 34% of Stage 1 assays have been returned, painting a picture of the mineralisation that is emerging.

With no cut-off grade and no top-cut grade, the average grade of Total Rare Earth Oxides (TREO), yttrium and scandium is 498.7 ppm and compares with the material sent for gravity concentration beneficiation testing in November 2023.

As well as showing that the mineralisation is likely to be upgradeable with minimal selectivity, AHK says the results also demonstrate the consistency of the mineralisation, ultimately resulting in a low-cost bulk mineable resource. 

The results are further bolstered by economically significant by-product grades in titanium and zirconium. Raw, uncut titanium grades average 6,490.6ppm and go as high as 113,427.5ppm.

This work, together with geological logging and modelling of data, will inform AHK’s upcoming maiden resource, set to begin as soon as the full quantum of assay results are returned.


‘Exciting scale and development potential’

“As the Sandy Mitchell data comes in, the thing that jumps out at us is how consistent the mineralisation is,” AHK executive director Ben Emery says.

“We aren’t surprised by this because we’ve set out our initial 4,000km2 resource grid in the middle of a 100km2 prospective area.

“The ongoing consistency of grade gives us an added degree of confidence around Sandy Mitchell’s commercial development potential, particularly given the already strong recovery rates achieved through our first-round water-based beneficiation test work in November last year.

“The early success of these simple extraction methods to produce high-grade rare earth concentrates demonstrates the exciting scale and development potential of Sandy Mitchell as exploration continues.”


What’s next?

The ongoing receipt of assays is expected over the coming weeks, ahead of the anticipated resource estimate for Sandy Mitchell later this year.



This article was developed in collaboration with Ark Mines, 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.