ABx Group’s (ASX: ABX) 37-hole drilling campaign has expanded resource outline northwest of the Deep Leads high-grade rare earth element resource zone in Tasmania.
The company has received 316 assays from 37 holes that were the first drilled into the untested NW Block of its Deep Leads rare earth elements (REE) project, located 45 km west of Launceston.
Several intercepts were considerably thicker than usual and extend ABx’s REE mineralisation across the plateau.
High Dy+Tb enrichment
ABx’s rare earth strategy is to produce a mixed rare earth carbonate (MREC) that is enriched in dysprosium (Dy) and terbium (Tb), the two heavy rare earths with the highest supply risk. The Dy+Tb exceeds 4.3% of Deep Leads’ total rare earth oxides (TREO), which is the highest proportion of Dy and Tb of any clay-hosted rare earth resource in Australia and high by world standards.
Thick zones of high-grade ionic adsorption clay rare earths with such a high proportion of Dy+Tb are extremely rare.
Favourable ore geometry: ABx’s rare earths layer is typically 4 to 7 metres thick beneath 2 to 5 metres of clay and soil, which is ideal for restoring any mined areas to productive, fertile land.
“Drill results in the NW Block expand the resource outline for the Deep Leads high-grade rare earth zone and also enhance the areal extent from hole DL520,” Managing Director and CEO, Mark Cooksey, said.
“DL520 is one of the nearest existing drill holes and is also where rare earth extractions of over 50% were measured using low-acid (pH 4) conditions – confirmed in desorption tests by the Australian Nuclear Science and Technology Organisation (ANSTO) and in- house tests.”
Desorption Extraction Results from NW Block
Hole DL520 is the nearest hole in NW Block to these new holes that has been tested for extraction during desorption tests. In tests conducted by ANSTO and repeated at ABx’s facilities in Tasmania, extractions at pH 4 of well above 50% were obtained.
Clay-hosted rare earth deposits typically contain a mixture of ionic adsorption clay (IAC, the ionic component) and a non-ionic component. The rare earths in the ionic component can be leached using a low-cost desorption process.
Industry processing experts indicate that it is very difficult to economically extract rare earths from the non-ionic component. Thus, it is critical to have a high ionic proportion.
The ABx strategy is to produce a mixed rare earth carbonate that can be sold to rare earth separation plants, for conversion into separated rare earth oxides.
Numerous discussions with potential customers and investors have confirmed the particular strengths of the ABx rare earth deposits.
