THE BOURSE WHISPERER: Impact Minerals (ASX: IPT) completed a review of previous gold production data at the company’s Blackridge conglomerate-hosted gold project located about 30 kilometres north of Clermont in central Queensland.
Impact Minerals used previous data that had been recorded by the Geological Survey of Queensland from 82 small mine shafts, which the company said demonstrated that high-grade gold had been mined over an area of at least one square kilometre from surface to depths of up to 80 metres.
The distribution of the old shafts and mapping by the Geological Survey indicates that the high-grade zones occur in linear fault-controlled zones that were referred to by the original miners as ‘runs’.
Impact has received bulk sample results for gold it says has identified potential for further high-grade runs that have not been mined both closer to surface and deeper, further to the west beyond the limited mining depths achieved by the early miners.
The company has interpreted other gold results from bulk samples taken by previous workers, and by Impact, to indicate the potential for large volumes of lower grade gold between these high-grade runs as well as higher up in the sequence.
The company considers, together, all of this data demonstrates the large-scale potential of the gold bearing units at Blackridge, and further bulk samples are planned for this Quarter.
These samples will be mostly taken on granted Mining Lease 2385 which was recently purchased by Impact Minerals and has now been approved by the Minister for Mines in Queensland.
“All of this work indicates the potential for a large mineralised system at Blackridge,” Impact Minerals said in its ASX announcement.
“Further bulk samples are now required on a more systematic basis to determine the gold grade distribution close to surface.
“A program of work for this is being compiled and will be completed as soon as practicable.
“In addition, shallow drill holes are also required to help determine the effectiveness of drilling as a sampling medium.
“Work by companies such as Novo Resources Corporation in the emerging conglomerate-hosted gold province of the Pilbara region of Western Australia, has shown that very large samples may need to be processed in order to overcome the significant ‘nugget effect’ that is a major factor in the exploration for this style of deposit.
“Impact has shown that the nugget effect was an important factor affecting the results of previous exploration drilling at Blackridge.
“Accordingly, drilling may not be highly effective at Blackridge.
“However, the purchase of Mining Lease ML2386 has provided a strategic advantage by allowing very large samples to be taken where appropriate.”