Terrain Minerals has hauled up some remarkable rare earth samples from its Lort River project near Esperance in Western Australia’s Fraser Range region, after multi-element assay tests picked up head-turning grades of up to 9840 parts per million (ppm) total rare earth oxides (TREO).
The uber-high-grade 1-metre section was discovered within a broader zone of 8m grading 4037ppm TREO starting at only 23m depth.
High grades of 2362ppm neodymium and 647ppm praseodymium - comparable with many of the Brazilian ionic clay-hosted deposits - have also been picked up within the samples.
The company started out in January hunting big nickel and copper sulphides, guided by months of meticulous interpretation of highly detailed geophysical surveys, which had lit up five juicy conductor targets on the margins of a highly visible intrusive anomaly in the Fraser Range.
Two of the targets have now been tested with the truth detector and while the results failed to deliver any base metal surprises, the drill rig instead turned the exploration campaign on its head with the discovery of rare earth riches.
The company says the drill bit first jagged thick zones of rare earth elements (REE) mineralisation at 23m depth in a contact zone between the weathered bedrock and the fresh rock – an ideal geological spot for cost-effective, clay-hosted REE extraction.
The Lort River project covers 320 square kilometres across the Esperance region, which has established itself as something of a rare earths province.
Ten months ago, Terrain’s next-door neighbour OD6 Metals updated its massive mineral resource by almost 100 per cent to 682 million tonnes at 1338ppm TREO for 910,000 tonnes of contained TREO at its flagship Splinter Rock project near Esperance – just over two years since its market listing.
A little further east, Mt Ridley Mines has control over 168mt grading 1201ppm at its eponymous project.
Terrain has re-submitted samples from Lort River to Intertek’s assay labs to test for an ion exchange reaction using a chlorine solution. The test will determine whether the REE is ionic or otherwise, the outcome of which could affect the cost of recovery.
The company is also mapping the grounds to plot out the distribution of weathered materials at surface – known as a regolith map - using the reprocessed geological survey data to delineate the influencing structures.
Terrain’s upcoming air core drilling program will then focus on defining a REE exploration target, which it expects to announce in the second half of the year.
With more than 550 square kilometres of prospective tenements in the Albany-Fraser Range belt - one of WA’s most prospective and underexplored regions – Terrain has no shortage of options when it comes to exploration targets.
It should have not come as a complete surprise then that a company looking for base metals would end up discovering high-grade magnet metals instead.
It's just another day in the life of a junior explorer.
Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au
By James Pearson
