TSX-V-listed gold explorer and developer Aton Resources reports that, of ten samples taken at the Rodruin exploration project at the company’s 100%-owned Abu Marawat concession, in Egypt, four have been selected for additional fine grind whole ore leach tests after data indicated higher gold and silver recoveries for the finely ground samples.
The concession where the initial scoping level metallurgical test work is being undertaken, is located in the Arabian-Nubian Shield, about 200 km north of gold miner Centamin’s Sukari gold mine.
Aton has identified numerous gold and base metal exploration targets at Abu Marawat, including the Hamama deposit in the west, the Abu Marawat deposit in the northeast and the advanced Rodruin exploration prospect in the south of the concession.
Ten composite samples, representing the range of mineralisation types at Rodruin (eight oxide zone and two sulphide zone), underwent scoping test work.
The samples were composited from reverse circulation (RC) percussion drill hole samples, following which they were subjected to whole ore cyanide leach tests on received material where the samples did not undergo grinding.
The test results showed final gold recoveries ranging between 51.4% and 84.2%, after 48 hours of leaching. Silver recoveries ranged from 25.7% to 65.8%.
Of the four priority samples, Aton notes that the ROMO-132 sample showed the biggest increase in gold recovery in the finer sample with an increase of 26.6% gold and 17.3% silver recovered, compared with its unground equivalent.
The biggest increase in silver recovered was 32.1% for the finely ground ROMO-129 sample, compared with its unground equivalent.
Gold recoveries from the three finely ground oxide samples ranged between 87.5% and 89.5%, with silver recoveries at between 52.7% and 73.6%.
The finely ground sulphide sample had gold and silver recoveries of 81.5% and 55.8% respectively.
Whole ore cyanide leach tests indicate that all the Rodruin mineralisation types tested are treatable using a conventional carbon-in-leach (CIL) process.
Aton interim CEO and chairperson Bill Koutsouras says the initial scoping level metallurgical test work programme results from Rodruin are “very encouraging . . . indicating that all the different mineralisation styles at Rodruin, including both oxide and sulphide material, will be amenable to conventional CIL processing techniques.”
He adds that Aton is confident it will be able to increase these recoveries by enhancing the leaching conditions as it proceeds, and indications of the presence of coarse gold from some samples both confirm Aton’s geological interpretation of the presence of high-grade zones at Rodruin.
This, Koutsouras says, suggests that Aton may be able to further enhance gold recoveries with the inclusion of a gravity circuit.
“Preparations for the upcoming diamond drilling programme at Rodruin and Hamama East are continuing apace with road and pad construction well under way, as well as the construction of the new Rodruin exploration camp.
“We envisage the next phase of metallurgical test work will be undertaken once we have drill core available for testing.”