Transcription of Finance News Network Interview with the University of Tasmania Centre of Excellence in Ore Deposits, Distinguished Professor in Economic Geology, Ross LargeDonna Sawyer: Hello I’m Donna Sawyer from the Finance News Network and joining me from the University of Tasmania’s Centre of Excellence in Ore Deposits, is Distinguished Professor in Economic Geology, Ross Large. Ross welcome to FNN.
Prof Ross Large: Thank you very much.
Donna Sawyer: Let’s talk about invisible gold. What is it and how do you go about finding it?
Prof Ross Large: Invisible gold is very small particles of gold dissolved in the structure of pyrite. It’s very hard to detect because it’s sub-microscopic, you can’t even see it under a powerful microscope. But with the new laser ablation technology we’ve developed at CODES, we can actually measure the quantity and the size of the particulars in the pyrite, which is very important in terms of processing the gold ores.
Donna Sawyer: Tell me about laser ablation technology. What does it do?
Prof Ross Large: Well if you think that we take a small bit of the ore out of the ore body and we fire a laser at it, and that laser ablates or dissolves the sulphide material. It goes into a little cloud that goes into the mass spectrometer, it’s immediately analysed for about 35 elements including gold. And that gives an analysis then on how much gold is in that particular grain of sulphide. And by rastering the laser, that’s just going back and forth with a laser across a part of the ore, we can actually find the little micro grains of gold that are invisible to other techniques.
Donna Sawyer: Commercially, what does this mean for goldmining companies and investors?
Prof Ross Large: Well it means that a lot of the lower grade deposits have this invisible gold and its referred to as refractory gold by the metallurgists, because it’s very difficult to recover from the ores. You need more expensive processes that use more energy consumption and therefore, a number of these deposits have not been developed. So if we can crack the invisible gold problem from a metallurgical point of view, then it would mean that a lot of otherwise uneconomical deposits can become economic.
Donna Sawyer: So what are the differences in problems associated with different ore body types, and why is that important for miners?
Prof Ross Large: Well gold generally is what we call free gold and that’s the small gold particles distributed through the ore body. And by
crushing and milling and gravity processes that gold is relatively easily recovered, it’s usually plus 85/90 per cent recovery. But these refractory gold systems with invisible gold are more difficult, sometimes they only achieve 70 per cent recovery. And therefore, a lot of that gold is going out into the tailings and being lost. But if through our technology, we can improve that recovery, just move it from 70 per cent to 80 per cent that
makes a major difference in terms of profits, for those companies.
Donna Sawyer: How do these new developments impact on gold exploration?
Prof Ross Large: They do in quite a different way actually. The gold that’s present in sulphides, particularly pyrite as refractory invisible gold, is also disseminated in the wall rocks around the deposit. Quite often it forms a halo around the deposit. And therefore, when you’re drilling for a new gold deposit, you may detect that pyrite with the invisible gold in the halo and it’ll give you information on where to put the next drill hole, to target the ore body. So it becomes what we call a vectoring tool in that it helps us vector, right into where the gold is within the centre of the ore deposits.
Donna Sawyer: So how can companies access this type of exploration tool?
Prof Ross Large: Well at CODES we’ve set up a special laboratory now that is a semi commercial laboratory, that’s doing work for the industry. We have three laser ablation machines that are devoted to research and that’s where the technologies come from. But now we want to roll that technology out so it’s available to industry. And Newcrest
(ASX:NCM) have put funding in that laboratory to allow us to set it up, and so it’s now available for companies to access.
Donna Sawyer: Currently CODES has three laser ablation units and have spent years working towards developing its wider ores focus. What
differentiates your approach from others?
Prof Ross Large: Well these laser ablation ICP-MS units are becoming more common around the world, but very few of them are devoted to sulphide ore bodies and the problems with refractory gold. But we’ve made sure that two out of the four of our units, are devoted to research and service work on invisible gold. And that’s what makes our laboratory so much different to others around the world. And it’s also the technology that we use in the laboratory. For instance, there’re only two laboratories in North America, one in the geological survey of Canada and one in one of the universities there that is doing equivalent work that we’re doing. There’re very few of those that are set up to tackle these problems.
Donna Sawyer: CODES works with a number of big mining companies. What are the benefits of investing into the type of research your facility does?
Prof Ross Large: Well the main benefit is that the companies have access to the new developments, as they come along. They can keep up to speed with these developments and see when they may be used within their operations. We also work with companies very closely. In some cases we have our research workers like Postdoctoral Fellows or PHD students, working within the company structure at the company ore body, or in their exploration location. So the transfer of our technology goes into the company system a lot quicker that way. And we’re very close as I said, with a number of our sponsor companies we call them, they’re the group of companies that are funding a lot of these developments, so that they can get benefit from them immediately.
Donna Sawyer: Are there any tax benefits for companies investing in this type of research?
Prof Ross Large: Yes there are. About two years ago, the Australian Government brought out an incentives scheme, tax scheme for research and development. And it’s mainly aimed at the smaller end of the market, but many of the junior and mid-tier companies can access that and get up to I think, about 45 per cent tax benefit.
Donna Sawyer: Finally Ross, what are you working on right now and what are you hoping to achieve in the coming year?
Prof Ross Large: Well I’m working on the invisible gold problem, but I also have other interests that you might say are more fundamental research. One of those is looking at trace elements in pyrite through time. We’ve got a major project where for the first time; we’re putting together the chemistry of the ocean from 3.5 billion years ago, to the present time. And we can only do that through these technological developments we have in our laboratory, where we can analyse pyrite now down to very low levels. We can analyse it in rocks that range from now to 3.5 billion years and actually reconstruct the chemistry of the ocean, exciting stuff.
Donna Sawyer: Professor Ross Large thanks for your time.
Prof Ross Large: It’s been a pleasure, thanks a lot.
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