Drilling at Oar Resources’ (ASX: OAR) Gibraltar halloysite-kaolin project on South Australia’s remote Eyre Peninsula has returned the highest grades of halloysite on record from any Australian project.
The “exceptional” results came from detailed x-ray diffraction (XRD) analysis of samples from a large zone of bright and ultra-bright white kaolinite.
Analysis generated individual grades as high as 53% halloysite from one composite sample.
It is the highest grade halloysite to be reported in the area, and believed to be the highest grade ever reported from an Australian project.
The individual result was combined with other holes which returned samples grading more than 30% halloysite and confirms the discovery of a new, high-grade project with “significant potential”.
High-priority target areas
Oar said the halloysite and previously-reported high-brightness kaolin results have highlighted four distinct high-priority target areas which will be the subject of additional infill drilling.
This “clustering” of halloysite pods within the broader kaolinitic saprolite is typical of Gibraltar’s style of mineralisation and has been observed in other halloysite-kaolin deposits within the district.
A large southwestern anomaly previously defined by high-brightness kaolin in scout drilling and now shown to also contain high-grade halloysite, covers more than 12 square kilometres and remains open and untested to the west.
Logging of drill chips from this target area has confirmed the presence of felsic granitic basement, which Oar has interpreted to be part of the same granite complex underlying the Mt Hope kaolin deposit owned by Andromeda Metals (ASX: ADN) and located immediately south of Gibraltar.
Oar has secured a contractor to commence systematic follow-up drill testing next month, aimed at better defining the target area and infilling additional “bullseye” anomalies as it moves towards the estimation of an initial JORC inferred resource.
Oar general manager of geology Tony Greenaway said the company is encouraged by the emerging cluster of halloysite pods at Gibraltar.
“We see this pattern over areas of a similar size on the Eyre Peninsula and [elsewhere] in Western Australia, where other companies have gone on to define very large resources based around similar early-stage drilling success,” he said.
“We believe we will continue to uncover additional mineralisation as we expand our drilling over the interpreted granite basement to the west and advance the target areas.”