The drill rods are spinning again for Oar Resources at the Gibraltar halloysite-kaolin project on South Australia’s Eyre Peninsula. A recently completed maiden air-core campaign netted kaolinite and high-grade halloysite up to 20 per cent in grade, with halloysite reported in 24 of the 59 holes drilled. Oar has now returned to the fray and is kicking up dust having commenced an aggressive 2,500-metre air-core drilling campaign to follow-up on the intriguing discovery.
A total of 47 holes will be completed on a 400m-by-400m grid pattern testing a 3.5-kilometre area located to the north of the recent discovery.
Last year’s maiden campaign of 59 holes for around 2,044m was designed around a single halloysite occurrence identified from historical reports. The drilling was completed on a 100m-by-100m grid pattern around the historic drill hole, widening out to 200m by 200m to the south. Further to the south again, another two scout lines of drilling were completed. The results did not disappoint.
Kaolinite presence was detected in all holes sampled, while high-grade halloysite was recorded in 24 of the 59 holes drilled, reaching grades up to 20 per cent halloysite.
Amongst other results, stand-out hits include 3m going an eye-catching 19.6 per cent halloysite and 42.4 per cent kaolinite from 26m depth, 3m at 10.1 per cent halloysite and 45.9 per cent kaolinite from just 11m, together with 13m at 5.3 per cent halloysite and 80.9 per cent kaolinite from 13m.
In a promising sign, the highest grade halloysite intercept of nearly 20 per cent was located at the end of a line of drilling appearing to leave the mineralisation open to the west and south of the intercept.
Similarly, approximately 2km to the south of the historic drill hole at the end of a scout line, the company appears to have identified an additional high-grade halloysite zone with grades in excess of 10 per cent.
With the Eyre Peninsula covered by a layer of calcrete cap masking the geology beneath, shallow and inexpensive the company considers air-core drilling best suited to developing an understanding of the regional geology. It also says it has the capacity to extend the drilling campaign depending on observations in the field.
Oar has submitted applications for additional drilling to the south, west and east of the maiden campaign with wide-spaced extensional drilling and reconnaissance drilling planned.
Industrial applications of halloysite are numerous including feedstock for high purity alumina used in smartphone screens, controlled release drug delivery, carbon capture and medical-grade ceramics.
Halloysite is a rare derivative of kaolinite and according to the company fetches a considerably higher price in industrial applications. The high proportion of samples containing halloysite from the maiden drilling campaign appears to provide further optimism for Gibraltar’s potential to host mineral riches.
What started for Oar as one historic drill-hole showing halloysite mineralisation has taken a significant turn towards the interesting. Just how big Gibraltar remains to be seen but a few pulses are likely to quicken as the company returns to smash out the metres in the hunt for more high-grade returns.
Is your ASX-listed company doing something interesting? Contact: matt.birney@businessnews.com.au
By Matt Birney
