right out let's get into met travel we are going to cover metal urge today and uh oh we had to we had to call in some help for this one mate what are you talking about you are a metallurgist you well when you started asking uh questions about right what's the difference between grabbing and and Cyanide and I started explaining and then realized that holy there's some gaps in my uh understanding and knowledge here and pretty much the whole thing so we've actually employed the help of a an expert metallurgist and yeah based on the theme of our show we can't anonymity is the key to the mystery of money of mine and can I tell you what I know about met as just a bloody a um a finance guy I know that if the Net's no good you're stuffed pretty much that's all I know and if higher percentage recovery is good yeah simple as that right is that all I need to know where is the gray areas and I asked uh this gentleman who is the most famous metal urgist in history like if we're going to give uh we've already doubted Mr Specter as the uh as our lawyer assistants based on Mr Harvey Specter doesn't watch seeds but ah yeah I've probably been salted by it so I found a book the first ever book that was written on Metallurgy you'll see it on here I think it was in like the 1500s uh by Georgie Agricola so Mr Agricola Mr Agricola is the metallurgist that uh helped us out here so now this is in relation to gas going they've put out their met results for the Never Never deposit the market was waiting for this one right yes because I think it's until you got you can have the greatest deposit in history greatest grade and everything but if you can't process it or you can process it but you're getting 80 recovery yeah it doesn't become that good and the context for gascoigne is when our you know processing their ore from the Ghibli pit they were only getting 80 odd percent recovery on that one yeah so the Market's a bit like hang on we want to see what the recovery is on this new deposit don't they yeah and then you've got the so they've put out that they've got 90 uh 92 plus percent so if we go down to the thing so it comes out it averaged at 92 for the oxide or and around 94 percent for a fresh rock so let's differences oxidor is up the top of the mine closer to the surface it's been weathered by history and everything so it's that's what an oxide thing is there's no not many sulfides or anything like that it's very weathered and exposed where then you've got fresh rock which is downdate solid in the ground probably contains sulfides and other deleterious elements possibly so gotcha so you're a Geo as well mate so apparently apparently so now we get into the Met results in that you see the 2K terms are gravity yep and say IL so Cil is carbon in leech that's the cyanide process so um and then and these are the two different ways of extracting the gold yeah they're two different ways but they're um this CIO comes after the gravity the gravity so not not all historic Mills would have had a gravity circuit so the gravity circuit is to get the free Milling gold the easy gold out after so so it goes through the crushing system now goes into circuit to extract the gold out the the gravity circuit gets the easy stuff that's there already the free they call it free Milling so you like it's like you like you get it for free you don't um you don't need a a lot of chemicals and you don't need to leave it in there for two days in the circuit to get to get the gold out so that's what the gravity circuit's for so so something more environmentally friendly too because you know yeah it's just quicker it's out of the circuit it's done you've got it yeah and it doesn't need to stay in there if it's already been extracted so usually the first gold bar that a mine pause will be a gravity gold bar because that's the first gold that comes out so if you look at their results here you'll see two sections so the fresh there so the average so they're based on the test that they did so what they got nine tests there um based on so the average head grade of what they've put in of those tests is seven grams and from that that dirt that went in in the fresh rock 34 of that was recovered in the gull the gravity circuit yep so then there's obviously what's what's left over then goes into the cyanide circuit and so for 48 hours so 48 hour cyanide recovery is 60.8 and this is when you're at a gold mine you see those giant tanks right that's what this part part of the processing is right there's yeah those those big giant tanks of the yeah that'd be the leech tanks and the absorption tanks and we'll go into what what they are so um now so as I said overall recovery 94.7 but then you look at you've got to look at that 48 hour tile so that's saying that when it's sitting in that cyanide circuit how many grams a ton are you losing that's going out to the tailing stem because when it goes through the gravity circuit uh yeah I'm pretty sure you're not sending anything out to tail it's when it's going because everything that doesn't get consumed in the gravity circuit would then fade back into the sign item pretty sure on that but um I can't make any assumptions here because I'm usually bloody wrong but I'm sure I'm sure Mr Agricola will get in touch and correct me so they're losing like 0.29 yeah so that's same for that's seven grams yeah you are losing the the tailings yep that's going out that's pumped to the tailings dam the big storage area that is grading 0.3 grams so you hear of some mines that use historical tailings or go and reprocess tailings and or use old tailings as a supplementary feed into the mill and things like that that's because there is like a grade in the Target yes yeah so then using processing altars I remember when Heron were going to process old tails and all that which is which marked it with a bit of disaster I think there's some some people trying to introduce new processing methods to extract the gold from those tailings even though there's these you know complicated issues with the cyanide and all that sort of stuff exactly but then the the all when mines were hot mined at such a higher grade yeah then the tailings are actually quite hard right now high grade in today's times so um but not in this case so you look at um so I point three they're losing 0.3 grams so that 94.7 overall then says it then says you're getting 92 percent of recovery from the cyanide circuit so they're Legend 0.3 so it's 0.3 I mean at a head grade of 7.14 you're losing zero point two nine you think that's all right yeah so solid result if you're getting 94 recovery so and then you because you go down to the oxide so notoriously oxide is easier to process because it's that's where I guess a lot of your free Milling gold is it's not there's no sulfides there encapsulating it and all that so your oxide's a lot easier oxide's close to the surface yeah yeah but it's because it's been weathered so it's sort of bit of work's been done on it already but as I said here like the oxide grade that they're processed here so they're only losing 0.16 grams in the cyanide circuit for the oxide material but the grade's only 1.59 yeah because it's never never the good stuff's yeah but I think this is some of the oxide material close to the surface for never yeah by the high grade is it underground underground yeah yeah yeah yeah gotcha gotcha so because you see the the only high grade three gram sample for the oxide material yeah so um yeah so they're the results so let's go through these circuits so you've got the gravity circuit you've got the cyanide turkey we'll start on the gravity so now you know gold is a very dense metal it's it's heavy like very heavy for its volume so the gravity the gravity circuit the purpose of it is to take that heavier material which is the like the the free Milling gold particles that are not contained within the sulfides and they'll come out of a um they're called Cyclones it's like where the Cyclones bloody spin it all up in the it helps separate the different types of yeah different materials separates it based on particles cycle size okay yeah and also separates it on density as well so which is specific gravity and also particle shapes as well so look the the Cyclone overflow that is what has been the material that's been ground up fine it's a it's a normal density and it goes straight to the the Cil circuit contained which is what contains the the carbon and the cyanide cell but then the underflow of the Cyclone which the other stuff that isn't in the Overflow so that is either coarse material or it's also the smaller material that is very dense so that's and that material the underflow is what gets either most of it is gets sent back to the crushing circuit to get grinded down further then so then it comes back to go out of the Overflow and into the into the cyanide circuit but the first it goes over this screen right under flight so that screen it's like the number I've been given is 2.4 millimeters so that course and dense material goes over this screen and then the finer material which is you would assume the dense fine material So based on gold being a very heavy metal you would assume that that finer material that's coming out of the Overflow is what contains my skull right because it's because it's dense dense so that material then falls through that screen and goes into the gravity concentrator so what's a gravity concentrator well a gravity concentrate it's like a big washing machine oh yeah so it um spins it around the heavy heavy guards called on the side of it that's the froy gold they then they then get that Ultra heavy stuff smash it with saw and odd and then in either an inline leech reactor and I ilr or an acacia reactor and I said it's still cyanide used in the three Milling process as well yes but it just doesn't sit there yeah that's how they but it's but the term the time and the amount of cyanide because you the amount of material is a lot better than running it through the whole back end of the circuit yeah yeah okay so then so the purpose of it is it's quick it's the first stage of the circuit uses a lot less chemicals um you don't need carbon activated carbon will go on to what that is and you don't need to leave it in the circuit for two days so it's um yeah then you got to I can't I can't confirm if it uses a lot less cyanide per amount but okay it's speculated wood right if it's not Sid speculate you would speculate because it's not staying in these yeah like big tanks yeah and going through so many circuits to get it out so I would assume you use a lot less cyanide um I thought you're a mining engineer mate yeah a lot of assumptions here so now the cyanide part of it so say you've got that's your gravity feed so that's the um so if you look at when it's going through that circuit the Never Never or 34 of the gold has come out in that circuit yep okay so now you're left with the rest goes to the retina so that goes to the cyanide circuit so I guess we should first explain I guess we'll go through what cyanide is but here's the the basic process so Cyclone gold the gold in the oil comes out the Cyclone overflow so remember the underflow is where it goes to the gravity circuit overflow will then go to this leaching circuit so gold the cyanide is what dissolves the gold into a solution can I tell you as a finance guy what I know about cyanide well it's not good it's bad for environment yes yes that's all I know yes it's um yeah don't smell it so then that golden solution goes is attaches onto activated carbon then the gold is then stripped back off that carbon and then they Electro win it and make gold bars so 85 to 92 percent gold that's your Dore bars then that goes to the mint uh so like a lecture winning that's how how they get this gold off the carbon is um outside nights are stripped off the carbon first into lu8 which is a hot concentrated cyanide then to get that gold out of that final concentrated sign or they Electro win it so they pass an electric current through the solution and cause the gold causes the Gold to plight out on those steel wool cathodes yeah that's I literally don't know this this is amazing to me so the gold before it's a bloody bar it says little carbon looking spectacles well and we'll get it now because it attaches to the carbon so that's how they extract it from the cyanide so because the whole purpose of cyanide cyanide is one of the few chemicals in the world that can actually dissolve gold so it just I'm sure they'd use something less environmentally bad if they could it must be the uh it must be the best best option so one and so once it's actually they they promote that gold Cyanide and oxygen so that creates uh this gold cyanide solution so you need oxygen you need all that they need oxygen cyanide to make it be out to get it to be able to Leach so as I said in the diagram here it's the it's like dissolving sugar in a cup of water so the sugar is the gold the water is the cyanide and it creates a creates a solution like that so but then there's they've got to take into account the acidity of it as well so for for this leaching process to work they need to it needs to be a high pH so they then add lime as well like the lime we're talking about how they were dealing with the acidic hydrogen uh sulfide water at Capricorn they were adding lime to The Ponds to try and lift the pH this is exactly what it is here too so for this leaching to work the pH has to be between I think it's 10.2 to 10.5 uh for normal water that isn't salty so if it's too light the leaching doesn't work now okay here's an example of the tank setup so this is a example of a setup from a mine of how this hole works so you see the you see the gray for all the YouTube watches you've got there's two big gray tanks so they're the big ones that you're talking about and then you've got you've got seven small tanks so the purpose of those two first big tanks is that's where the that's where the cyanide is intro introduced the cyanide mixes with the crushed all that contains the gold and that's what um that's what creates the the cyanide solution then once it gets to the first of the absorption tanks so the two big ones are leech tanks that's where they added in to correct the solutions that's just Cyanide and oxygen they then go into the absorption absorption tanks can you explain the difference between absorption and absorption now so once it gets to these absorption tanks sorry adsorption tanks not absorption as you corrected me there is a difference I AB absorption absorption means it all mixes together I think whereas adsorption means it sticks onto it it's like it adhes it adhes yeah so it's an easy one to uh look at at the pronunciation I think I said absorptions before so it's actually adsorption so that's where the carbon is put in and the cyanide solution the gold add attaches to the carbon so and that's where that whole that's where so you got the first two don't have carbon the two big tanks the seven big ones after this in this example have the carbon put into it so now what's the activated carbon so funnily enough I found out this activated carbon is made from coconut shells right what have you thought that what do you mean activated carbon okay so it's activated so this activated carbon it's a it's a very the purpose of it is it it attracts to the the cyanide and the gold attract to it and latch onto it and it has a very high surface area so it's obviously very light and poresy so and all the solution mixes into it and attaches to it so it says here that one gram of activated carbon has a surface area of in excess of three thousand square meters oh wow that is bloody phenomenal because I think carbon's pretty light isn't it yeah so the pencils yeah so that that is what it does so it's saying that one gram of carbon can load up to 30 to 35 kilos of gold that's pretty uh that's pretty pretty phenomenal so that carbon and you say in the diagram here so you see the flow there so you've got the slurry which is the the gold cyanide solution that flows through the tanks in the left to right one two and three but the the carbon is actually put in the other way and flows against it so which creates that um movement interface for the where the gold then attaches right to the car so when you see there's like these seven tanks on site they're not just trying to look cool by having more there's a reason yes yes and there's it would depend on the plant the amount of feed because the there would be a tie you'd need a certain time in the circuit per the volume in so many variables to make sure that you get all the gold out at or as much gold out and you're not sending it out to the tailings dam so now if you look at that's obviously overview or the flow sheet the process a very very un non-medological overview from someone so be bloody kind in your comments so never never so as I said here they've averaged 92 overall recovery in oxide material and 94 in the standard gravity carbon in leech process so sorry average 94 so in the holders standard gravity carbon in Leach process that's the flow sheet that you talked about the real question I have mate is do they have the the plant as it is in in dalgaranga is it already configured to process in this way well if you look at um their comments they say that their current five-year-old two and a half million ton plant so the existing soil process plant fly sheet is well suited in its current configuration right so to process the Never Never high grade material yep so then the combination circuit is suitable so common I'm pretty sure that's how you pronounce a combination that's the crushing Circle that's how they crush it all up so that's suitable with uh with upgrades as indicated in the original dangara dalagaranga DFS gotcha so they might need some upgrades that are highlighted in that DFS they've already been highlighted yeah so nothing new um but not much now gravity gravity leaching gold recovery tailings and Plant Services are fit for purpose and only require minor refurbishment to start up so yeah um and then what you probably can expect after a care and maintenance period so the existing sale circuit capacity is adequate at the anticipated treatment rates okay so it's but there's a there's a bit we'll go through a bit in the next steps so now I guess there's a the comment before that is where your stuff that you've probably got to look out for when you're looking at recovery so you've got overall gravity recoveries is 34 in uh 20 in the oxide and 34 in fresh material so that good or bad that's I think it's well it's good that you can actually recover through gravity yeah um but you obviously want the higher that you want as much as possible you want as much as possible so but the fact you can get some out in the gravity circuit means yeah good it doesn't have to go on the cyanide circuit less cyanide less carbon um lower cost how does it compare to other other gold Wines in wa well the standout that I've found here is Bellevue okay so Bellevue is this always a standout this was this was pointed out by Mr agrically I think it was that how you pronounce it I've forgotten the name already sounds really quite right look if you look at bellevue's initial met results they put out in 2020 so their overall gravity and Leach recoveries of 97.8 so they've got a lot higher recovery total yeah but the the real standout is their gravity component only so their gravity component was 73.6 to 91.7 so that is saying that 70 over three quarters to nearly 90 of the gold is gravity out of the gravity circuit so it's all free Milling gold or most of it is and then if you look at the and that saves money yeah yeah so you I would anticipate to be able to I don't know if you'd be able to increase your throughput right but Bellevue are on a different scarce there I think there are a bit over a million ton per annum so yeah um not as much as going through oh great on their side too but yeah good good net to go with it and then so if you look at if you look at their results how they are reported their um results similarly our gascoigne have yeah it actually shows how quick it came out of the circuit so if you look look there for let's just look at uh Tribune uh so they're 92 recovery at 92 percent of it was recovered by gravity yeah that's a head grade of um 21 Grams 92 come out of the gravity circuit then within the first eight hours it was at 99 of that was cut recovered in the cyanide so that's saying it's it doesn't appear to be staying in circuit and gas coin only report that 48 hour mark which which gives me an indication that it takes longer in the sign yeah yeah it maybe does hear about Visa would you would you read that yeah gascon they've definitely reported it a bit different so they've reported on um 48 Hours only whereas Bellevue of shown how quick it gets into a higher recovery over these eight hour increments so look you could interpret it that you could interpret that it takes longer for gas going to recover it in the cyanide but because because I haven't reported the ideas so you could see say it's it takes them 48 hours to um get it to that high recovery level or because I haven't reported it in that eight hour increment they they could actually be getting to that 94 recovery quicker than 48 hours which would be a positive it just looks like they've gone for 48 hours chucked it in see what we get after 48 but they could actually be getting there earlier but we don't know because I guess the data isn't there they haven't reported it in those eight hour increments like Bellevue did so it's um this was yeah Bellevue appears to be a real standout in terms of how much they can recover through gravity um and which is you know great great for their Milling grade for their recovery especially if you're getting an extra four percent recovery over on a 10 gram or body it's gonna be um very 10 gram resource sorry it's going to be uh very favorable so Maddie you had you had a fun fact for me about refractory orebodies today as well I didn't know about well refractory is like the term and this is something Mr Agricola has uh confirmed for me which I was I was on the always enemy head oh a refractory that's um means it's fully encapsulated in so far it's needs to be needs to be burned off but I'll tell you what I I think of Refractories a finance guy mate oh good no good Capital yeah well I guess the term for the definition of refractory is a like refractory gold is a gold that doesn't respond to cyanide treatment yeah so I guess the the best way to talk about what what a refractory is is let's use a pistachio nut as an example Travis yeah like a you know you've got you've got this green nut that's your gold yeah and then you've got this this shell around it which is you would can be a sulfide it can be a arsenic now because you can look at you look at here so the gascoigne have made a comment no material or significant recovery issues from any deleterious elements that's other elements um copper lead thick nickel or arsenic in The High Ground material because what happens with arsenic so arsenic can actually if you have a high arsenic content that arsenic can just form this covering around all the fine gold party particles and you can like you can crush the living out of it down to the finest particle ever but you still can't fully expose the gold from all the Arsenic and the other deleterious elements so the best way to explain it is a pistachio nut so yeah so you've got that's covered in that shell so yeah uh you put that through the crusher you put a shitload of pistachio nuts through the crusher you know some sort of some have already been cracked right open and exposed put it through the put it through the crushing circuit it comes out and then even after all that crushing and everything you've got to have some some that are just fully exposed shells gone so that that's what would go into your gravity circuit that's you that's free Milling doesn't need much crush and it's straight out of your gravity circuit then if you go through your ones that are I guess partially mostly ripped open Chuck them through your cyanide circuit and then the cyanide and the carbon will attach to those and it's all open and there and it's got the room to attach to it and it pulls all the gold out whereas a refractory or body means that even after all that crushing you've ground them down so fine those nuts which are the gold are still fully encapsulated inside that pistachio the Shell's still on it the Shell's still on it it has its lock you haven't even cracked it so you can pump as much Cyanide and in there and bloody shitloads of carbon to try and get it but it just doesn't have an entrance to get it to get it out of that shell so and that's what uh that's what arsenic high arsenic can do so people would know that de gray is a refractory or body so refractory means it won't fully respond to this cyanide Leach process so it will need to go down the road of a like pressure oxidation or a roasting so yeah that that pressure oxidizing and roasting is what gets rid of all the around it to expose the fine gold particles so they can actually be extracted yeah but that's that's high capex the other way you've got the roaster I can add a barrel they've got a roaster there yeah yeah so it look and that thing it's the once it's got the capex it's like nickel laterites like yeah the high h-power plants there like they're they're high Capital but if you've got the all body to support it like which degree has like it's got a massive resource yeah and brings you justify it can justify that it's just a super pit refractory but they just grind it really really fine yeah I'm not sure I think it is yeah there you go I'm sure there's um mixture of refractory and free Milling yeah yeah um yeah but then I think it's once you're like true Refractories when you grind at that Bloody fine and that's still not enough then it's that yeah yeah so then you've and then another term they used in here no material or significant recoveries issue issues from any preg robbing preg Rob Craig Robin pregnant people I didn't even think of that too long though so such as material in graphic graffitic shell so what preg robbing is Trav is when you've got like graffitic shells like graphite is a carbon so they say that that that carbon you've got a higher carbon content in the gold ore that's going through so when they throw the carbon in there the cut the activated carbon all this carbonaceous material goes to the carbon first instead of the gold material so it's like a bit of a date it acts as a bit of a it's got the front row seat compared to the actual gold so if you've got a high amount of uh pregrowing material it means you would need either a shitload of carbon or it will not get all the gold out so you'll be ending sending more gold to the Tails because your whole carbon CIO process is not working efficiently so that's another Plus for this so I guess uh overall from uh Mr agricala he said that uh looks pretty solid the gas going met results in the fact that uh the the 48 hour thing is probably a bit higher when but when you look at what how quick Bellevue get it out but look yeah 94 recovery and look I guess the key message at the end what are the next steps and I guess what do they mean so refresh of the process design varying throughput rates and rate options and recovery so remember this is a two and a half two and a half million ton per annum it's a big meal yeah and you won't be able to I'd find it very hard to believe if you could Supply it from underground I could nearly say you won't be able to supply two and a half minutes they need to blend it with with ghiblies wouldn't they yeah but then you can you can blend it with ghiblies but then you're like okay two different deposits out how's that going to affect the overall recovery yeah blend it so they've got yoga as well yeah but then do you actually look at this throughput right and say right what if we run it at 1.8 to 2 million tons per year so he can still it just means it means you'd have to things would stay in circuit longer yeah um like so you'd be in the crush it circuit longer so you'd actually be able to grind it down finer will dropping the right grinding it further keeping it in circuit longer will that improve the overall recovery because if you've grounded down further and you leave it in the circuit for longer you've got you would anticipate that would give you more chance of extracting more gold but your unit Milling cost then goes up because you're effectively paying the same amount to process 2 million tonne as you would to process two and a half million times yeah so it's a big it's a big change will that will that extra Milling cost be offset by an increase in recovery this is what you talk about being mine constrained or Milling constrained exercise it would be mine constrained and they stay you know yeah your mind yeah you feed constrained yeah so that's um and I'm sure there's a lot of um analysis to be done there to see what's going to actually work for them so and then it says optimization study studies for in uh improvements in overall metallurgical recovery so there's there's improving it in its current state with just the Never Never but it's locked in there's a whole analysis right if we start out in the adding a bit of dust in from uh the ghibli's pit yeah will that um extra three put would be a detriment will it work outside I guess that's what we've got to wait and it's probably right consolidation opportunities there too if you if you if you've got better blend results than aquilities which is um yeah all that's caused a bit of trouble from recovery sensor I'm just blending with with other stuff that's not currently in the gas coin portfolio makes more sense too and I think that's um I guess people need to we all need to consider that when you're talking about Regional consolidation or toll trading agreements like just because there's a Mill close by the mineralogy of that dirt might be a detriment to the to the client's Milling like because when you'll mix it together it might actually um it might have a high arsenic or something it might introduce issues to their own recovery so um you would you would think that not every not every gold can just go to one mil it might be a depending on the mineralogy of each separate deposit will they work together it's something that needs to be that I'm sure is are talked about on a very high level between all these companies that are looking to toll trade or possibly do mergers so sometimes it might not work so oh there we go Trav Metallurgy so God I hope I did the uh did the field some justice today but I think you might be getting a job at gr engineering after today can I get a family discount or something might at least give us a bloody invite to the Christmas party or so I don't even get one there well there you go so uh thank you to Mr Agricola for uh giving me a bit of a bloody uh metallurgical advice there I'll just confirm it's bloody said that right haven't I it's agriculture we are confirming Agricola right on mate there we go the information contained in this episode of money of mine is of General nature only and does not take into account the objectives financial situation or needs of any particular person before making any investment decision you should consult with your financial advisor and consider how appropriate the advice is to your objectives financial situation and needs foreign [Music]