Gold Road grinds out higher recoveries at Gruyere

THE DRILL SERGEANT: Gold Road Resources (ASX: GOR) has received results of additional metallurgical testwork the company had conducted in response to recommendations made in a metallurgical report released in February.

 

Gruyere plan projection illustrating location of RC holes sampled
for Metallurgical testing composites. Source: Company announcement

 

The latest metallurgical testing has used a coarser grind size on samples from the company’s Gruyere gold project in Western Australia to produce recoveries in excess of 95 per cent at P80s of 106 micron and 125 micron with air sparging.

Using oxygen sparging increased leach kinetics and improved recovery by an additional one per cent to two percent.

Intermittent bottle roll tests simulating heap leach recovery produced rapid gold extraction of 70.3 per cent in 24 hours, levelling out at 81.2 per cent after 96 hours.

Gold Road indicated using a coarser grind size could result in lower capital and operating costs for the grinding circuit in any potential future processing plant as it would enable the company to reduce power consumption and increased throughput potential.

It also identified oxygen sparging as a potential method as it too could allow for reduced leach residence times and therefore reduced tank capacity requirements, while increasing gold recoveries.

“The latest metallurgical results support the likelihood of achieving high recoveries with the potential use of standard CIL processing commonly used in the Western Australian gold industry, and also support the use of the lower capital cost option of Heap Leach, both of which will be studied further,” Gold Road Resources chairman Ian Murray said in the company’s announcement to the Australian Securities Exchange.

“These results, combined with the current resource drilling program, should allow us to continue to rapidly add value to the Gruyere project.”

Further testwork recommended by the February report includes grind tests at 150 micron to investigate recovery behaviour at even coarser grind than has been tested to date.

Other testing will involve column tests for heap leach testing to confirm initial intermittent bottle roll test results as well as comminution testing to facilitate grinding mill calculations.

Email: perth@goldroad.com.au

Website:  www.goldroad.com.au