It appears that detecting gold, presumably for mining purposes, isn’t as easy as one might think especially at the nanoscale. Researchers at Australia’s University of Adelaide have devised a new method according to an April 29, 2015 news item on Nanowerk (Note: A link has been removed),
University of Adelaide researchers are 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.
Using light in two different processes (fluorescence and absorption), the researchers from the University’s Institute for Photonics and Advanced Sensing (IPAS), have been able to detect gold nanoparticles at detection limits 100 times lower than achievable under current methods.
An April 29, 2015 University of Adelaide news release details Australia’s interest in gold and offers a high level explanation of the need for better gold detection (Note: Links have been removed),
Australia is the world’s second largest gold producer, worth $13 billion in export earnings.
“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,” says postdoctoral researcher Dr Agnieszka Zuber, working on the project with 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.”
The researchers have been able to detect less than 100 parts per billion of gold in water. They are now testing using samples of real rock with initial promising results. The work is funded by the Deep Exploration Technologies Cooperative Research Centre.
The gold detection project is one of a series of projects which will be presented at the IPAS Minerals and Energy Sector Workshop today [April 29, 2015], aimed at linking resources specific research to local companies.
You can find out more about the University of Adelaide’s Institute of Photonics and Advanced Sensing here.