University of Adelaide researchers develop breakthrough gold detection method


A team of researchers from the University of Adelaide is working on developing a portable, highly sensitive method for gold detection that would allow mineral exploration companies to test for gold on-site at the drilling rig.

Image credit: User: Boykung
Image credit: User: Boykung

By using light in two different processes (fluorescence and absorption) as a gold detection method, the researchers from the University’s Institute for Photonics and Advanced Sensing (IPAS) managed to detect gold nanoparticles at detection limits 100 times lower than achievable under the current method.

“Gold is not just used for jewellery, it is in high demand for electronics and medical applications around the world, but exploration for gold is extremely challenging with a desire to detect very low concentrations of gold in host rocks,” said postdoctoral researcher Dr Agnieszka Zuber, who works on the project alongside Associate Professor Heike Ebendorff-Heidepriem.

“The presence of gold deep underground is estimated by analysis of rock particles coming out of the drilling holes. But current portable methods for detection are not sensitive enough, and the more sensitive methods require some weeks before results are available. This easy-to-use sensor will allow fast detection right at the drill rig with the amount of gold determined within an hour, at much lower cost.”

According to the news release by the University of Adelaide, the new detection method allowed the researchers to detect less than 100 parts per billion of gold in water. The method is now being tested on samples of real rock with initial promising results.

The gold detection project – which is funded by the Deep Exploration Technologies Cooperative Research Centre (DETCRC) – was one of the series of projects that were presented at the IPAS Minerals and Energy Sector Workshop on Wednesday.

Industry representatives attending the Workshop also had the opportunity to hear about the Photonics Catalyst Program, a joint State Government and IPAS initiative which supports connections between advanced photonics technologies and SA industry.

Manufacturing and Innovation Minister Kyam Maher says IPAS’s collaboration with partners was stimulating new technological discoveries to contribute to the State’s reputation as a knowledge economy.

“The Photonics Catalyst Program helps South Australian businesses, including resources-related companies, identify the emerging laser and sensor technologies that could transform their products or business models,” Mr Maher says.

“Technology plays a central role in the competitiveness of South Australian manufacturing, supporting innovation, driving product and service development and improving manufacturing performance. It will play a key role in driving change and will underpin the transformation of the South Australian economy.”