WA’s most recent rare earth explorer, Torian Resources has reconfirmed and upgraded significant yttrium and other heavy rare earth element grades at its exciting Yttria discovery at the company’s evolving Mt Stirling gold project in WA.
In its pursuit to gain a better understanding of the nature of the yttrium and heavy rare earth element, or “HREE” it has discovered, Torian resubmitted a selection of samples from the original 151 auger vacuum drilling program utilising a more appropriate extraction technique to greater reflect the grades intersected.
Initial laboratory analysis of the AV drill samples employed the aqua regia leach technique that only partially digests REE-bearing minerals.
Aqua regia is known to under-estimate metal grades but is used in the exploration sector as a cost-efficient first-pass assay tool.
Despite the under-estimation, first-pass analysis yielded concentrations up to 544 parts per million yttrium oxide. Interestingly, significant enrichment of dysprosium, terbium, europium and neodymium heavy rare earths along with cobalt, scandium, nickel, chrome, platinum and palladium were all mapped out over a strike length of 1 kilometre.
According to the company, 21 samples from Yttria have been re-analysed using a mixed acid digestion under high pressure at a temperature of about 180 degrees celsius in sealed teflon vessels by microwave digestion with an inductively coupled plasma mass spectrometry – “ICP-MS” analysis.
The reanalysis of the samples has reportedly yielded yttrium concentrations up to 687 ppm yttrium oxide.
Additionally, previously unreported heavy rare earth oxide and yttrium oxide, or “HREYO” concentrations peaked within the regolith-hosted system at an impressive 1141 ppm.
Added to the mix bag of elements is anomalous values of scandium with values grading up to 110 ppm, compared with 76 ppm reported from previous aqua regia analysis.
Taking into consideration the improved assay values, Torian says all samples from the Yttria prospect have been resubmitted for fusion extraction and ICP-MS analysis, that enables the highest level of extraction to achieve optimal results.
The company said its focus on the presence of yttrium in surface soil samples was initially to guide AV drilling for gold exploration.
Intriguingly, yttrium is also an excellent pathfinder for the high-value and rare HRREs.
Torian sought the expertise of Professor Ken Collerson during the evaluation process. Professor Collerson has extensive experience exploring and studying REE deposits in Australia and abroad.
The work has identified the mineralised system at Yttria is “quite unique” given the high proportion of HREYO in the regolith and likened the geological setting at Yttria with Lynas Rare Earths’ Mt Weld REE deposit, that is also located in the northern reaches of Western Australia’s Yilgarn Craton.
As Torian continues to expand the footprint of the regolith-hosted mineral system at Yttria with a dedicated AV rig no doubt neighbouring explorers will be casting a wistful eye over their own tenure in light of the critical HREE discovery.
Torian Resources Executive Chairman, Paul Summers said: “Our recent gold results confirm our continuing effort with gold exploration at the Mt Stirling Project. Our resource continues to expand, with significant positive results towards our upcoming MRE.”
“To now have further confirmation of what is clearly becoming a binary focus of the Company in both gold and rare earths has increased the excitement of our dedicated team. This latter unexpected discovery appears to be exceptional and we eagerly await upcoming assays and RC drilling to further define the magnitude of the Yttria discovery.”
China currently produces the lion’s share of the world’s rare earth metals, crucial to the manufacturing and development of many technologies that are seen as crucial for the modern economy. The geopolitical risk to the global supply chain is obvious given China’s currently fractured relationship with many parts of the west. This has meant many parts of the world are scrambling for alternate avenues for supply.
Torian finds itself in an enviable position having topped up its coffers to over $4.2 million courtesy of a recent option conversion. A timely move as the company ramps up exploration over both its globally important Yttria REE discovery and the developing high-grade Mt Stirling gold project.
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