East Star Resources PLC (LSE:EST) said it has completed a 1,001-metre (m) reverse circulation drilling programme at the Talairyk heavy rare earths project in Kazakhstan.
Around 90% of the boreholes recorded broad kaolinitic clay zones between 9m and 53m, averaging 32m thickness, said the London-listed exploration company. Kaolinitic clay can potentially host high value heavy rare earth elements (HREE) that can be easily extracted via relatively benign leach solutions.
'We are pleased to have been able to complete this programme this year so the assay and leach test work can be undertaken over the winter,” said chief executive Alex Walker.
The drilling programme, which was brought forward several months, was designed to confirm historical grades and provide samples for metallurgical test work.
Historical estimates suggest the presence of elevated grades of total rare earth oxides (TREO) including yttrium (Y) oxide in a zone approximately 20m thick at an average depth of 7.5m from the surface.
“Broad zones of kaolinitic clays are exactly what we hoped to see as this is the minerology where an ion exchange style REE+Y deposit might develop,” said Walker. “If the results prove positive, we can launch straight into a dual strategy of resource and exploration drilling at the Talairyk project in 2023."
Drilling covered the southwestern part of the Ionic Adsorption Clay (IAC) hosted deposit.
Potentially economically extractible IACs are rarely found outside of South China. IAC deposits have several advantages over the more commonly occurring hard rock REE deposits, including lower capital and operating expenditure, negligible radioactivity, and a higher average basket price.