Bradda Head Holdings Ltd (AIM:BHL) reported positive drilling results from its Burro Creek East litium project in Arizona that it said could potentially lead to an increase in resource size and to a higher confidence classification.
Assay results from the first twinned holes (BCE21-01 and BCE21-02) at the Burro Creek East deposit show the potential for higher lithium grades in the Upper Clay Zone versus a 2018 drilling programme.
The Lower Clay Zone has also been intercepted and found to be variably mineralised with lithium. The Lower Zone was not tested at these two locations in 2018, partly due to budget constraints, and so was not included in a 2018 resource calculation.
Assay results from the completed portion of a second twinned hole (BCE21-02) showed a 14% increase in grade in the top part of the Upper Clay Zone over the same depth profile, with the highest grade recorded 1,840 parts per million (ppm) over 1.2 metres. However, mechanical issues with the drill rig meant that hole BCE21-02 was terminated earlier than planned and before reaching the depth of the previous 2018 Reverse Circulation (RC) hole.
“This increase in grade is highly encouraging and may indicate that some mineralisation was previously missed due to zones of low recovery during the 2018 RC programme, which can be the case with RC drilling. If so, this may have positive implications for resource grades in some areas,” the AIM-quoted company said.
Hole BCE21-01 also discovered previously unknown, but anticipated, lithium mineralisation within the Lower Clay Zone. The 2018 RC hole was not drilled deep enough to test the Lower Clay Zone at this site and so was not included in the 2018 resource calculation. The highest lithium grades recorded at hole BCE21-01 is 1,410 ppm over 1.5 metres in the Upper Clay Zone, and 1,020 ppm over 1.4 metres in the Lower Clay Zone.
A replacement drill rig started work on August 23 to accelerate the exploration programme. Bradda Head aims to complete the remaining holes within 30 days and receive all assay results by the end of October.
"These initial positive drilling results confirm our 2018 programme at Burro Creek East, and we believe, have the potential to add further resources to our previously reported numbers,” said chief executive Charles FitzRoy.
“The presence of lithium mineralisation in the Lower Clay Zone reinforces our geological model for the Burro Creek lithium deposit and bodes well for the remaining drilling programme.”