You are right about one thing, I have a VB in my hand. Pity I haven't drank a slab LOL before deciding to reply.
General
So where do i start. Ok, if your comparing deposits there are a few factors to take into account - some of which is in this post: Post #:
38263288.
1. Grade of resource - AVZ grade is about 1.6%, compared to 1.26% PLS (or 27% more revenue,all other factors been equal, from each tonne of installed ore capacity). Grade (as well as waste to ore ratio) IMO also impacts recovery rates and quality of spodumene.
2. Waste to ore ratio - AVZ waste to ore ratio is 1:1 by the looks of it, compared to over 4:1 for PLS. read less costs.
3. Before rabbiting on 1 and 2, some background on what you do with your resource. You have essentially a floatation process in effect for producing spodumene concentrate and then, for example, a roasting process at 1050 degrees celsius to produce lithium carbonate (i.e. a bit more complicated than that but want to keep it simple). These processes themselves are about reducing the iron/impurities in your ore so that you have battery grade product for the EV market. Now the more you reduce the impurities in your spodumene concentrate process the better price you receive, i.e. just because a deposit say grades say 1% Fe203 doesn't mean your product sale will be that because the process flowsheet in spodumene is aimed at producing your concentrate but removing your impurities, an obvious point -
https://www.sgs.com/~/media/Global/...-WA109-Hard-Rock-Lithium-Processing-EN-11.pdf
4. For AVZ it requires 5 tonnes of ore at a 80% recovery rate at a 1.5% Li20 ore content to produce 1 tonne 6% grade spodumene (6.2 tonnes for PLS at 1.26% Li20 content at 77% recovery rate). It takes 7.5 tonnes of 6% grade spodumene to produce 1 tonne lithium carbonate, hence where the power requirements are as one step in that lithium carbonate process is roasting at 1050 degrees. And you don't want to be removing more impurities than you have to
5. 6% grade spodumene effectively means that 75% of he concentrate is spodumene. 6.5% spodumene means 81% of the spodumene concentrate is spodumene. hence why grade is king - it means you can produce a higher grade product, and through that itself reduce the impurities within it
How do impurities impact the converters
The more impurities you have in the spodumene concentrate in the roasting process, you will need to extract these impurities out but you also extract out lithium, a problem in itself. Impurities forms 'clinkers', and then you need to run a process to get the lithium out of the clinkers and you might only get 75% of that from the clinkers, and that affects the recovery of lithium overall in the roasting process and impacts the ability to produce battery grade carbonate. Best explained in this article:
https://www.linkedin.com/pulse/all-chemical-grade-spodumene-concentrates-same-harman-grant/
Teachnical grade lithium - a key
Technical grade concentrate (used in glass/ceramics) has a lower iron content than chemical grade lithium (used in batteries). Technical grade can be used for chemical grade purposes but chemical grade cannot be used for technical grade purposes. Obviously if you have low iron content you are well placed to enter the lithium hydroxide market as well. Refer post - Post #:
37867119 and Post #:
38039838
The iron content in Technical Grade concentrate (say what Greenbushes sells in addition to its Chemical Grade sales) is required to be maximium 1%, but preferably much less than that IMO, which then converters use to refine (and further reduce the impurities, for the glass and ceramics industry). It would appear to me if your TG concentrates have higher than higher than 0.75% Fe203 they will not be processed for use in glass and ceramics industry IMO
See artciles below for details:
http://www.breakawaydigger.com/Article Digger November 2015/Article 7 November.pdf
https://www.weare121.com/blog/a-lithium-primer/
Chemical grade lithium
For chemical grade lithium, you want to be aiming for 1% to 1.5% Fe203 tops, probably closer to 1%, in your chemical grade spodumene concentrate IMO to extract the best price.
Best explained in this article btw, and it is an easy read - need to copy link into firefox and read introduction. If your spodumene is say at 1.5% (or slightly above) the probability of that spodumene been used in the hydroxide market IMO is greatly reduced IMO (even after the downstream converter process IMO), but fundamentally you are not going to get a high price for that sale because it is going to cost the converter money in the roasting process to get it to battery grade, and that might have its own difficulties in doing so IMO.
https://books.google.com.au/books?i...03 content in spodumene batteries&f=false
The links below explain this further:
https://www.911metallurgist.com/blog/froth-flotation-spodumene-processing-lithium-extraction
Obviously the roasting process significantly reduces the deleterious elements in the concentrate but they come at a high cost (read you get a lower price for your spodumene sales) and in some cases I suspect you still can't reduce to the required specs (noting iron is only one of the elements you need to get to the required range).
Here are the specs for battery grade lithium carbonate and Fe is in PPM terms at 10 or essentially 0.001%,with LiCO3 been 99.5%:
http://palith.com/english/product/index.php?act=&sid=23
For hydroxide battery grade impurities need to be less:
https://livent.com/wp-content/uploads/2018/09/QS-PDS-1021-r3.pdf
So how much Fe203 is likely to be in the AVZ concentrate
The best place to start for AVZ is the initial Ann of 2 August 2018 page 7 - Post #:
34683622. The mean concentration in the ore was 0.90% for Fe203, with the 80 samples giving a range 0.63% - 1.17%. The Ann stated that this was derived using a " simple flotation and magnetic separation" process (note the word simple). It will be interesting what the latest MET tests show. Need to say though, when you look at Greenbushes which is a high grade deposit (albeit it has a higher strip ratio to AVZ but better than PLS) not surprised you can get this, but the proof in the pudding will be what a full scale plant comes in at. That is always the issue - how do MET/pilot results correspond to the actual spodumene production configuration
Ironically for AVZ the concentration came in at the 'ore grade level' as the ore itself grades around 0.90% Fe203 - page 4 Obviously a good start for producing a low iron spodumene concentrate product given the strip ratio (point 2 above) and good grade.
Essentially what I am saying is if you start with low iron in the ore, have high grade ore containing Li20 and a good waste to ore ratio (increasing the possibility of producing a spodumene concentrate above 6%, the likelihood is that the concentrate will have a low impurities content, with Fe203 around hopefully 1% (meaning the offshore converters have something to work with). My hunch.
PLS
So I'll come to PLS and I am sure I am going to get shot here - despite the lower Li20 grade to AVZ (albeit better than say MIN and AJM) and noting the higher strip ratio compared to AVZ (and therefore greater work in the spodumene process itself for producing nice spodumene), and despite its own Anns saying the iron in its ore may be comparable to AVZ, in reality the latest PLS Ann - page 7 - dated 1 May 2019 - Post #:
38343163 - states the iron content in its spodumene sales is around 1.8% (meaning extra costs at the converter level to remove these so as to get it to battery grade applications IMO).
The high iron content in the chemical grade spodumene sales is probably one reason IMO the price PLS has recently got for its sales is closer to the US$650 per tonne mark. I note, its earlier shipments of spodumene in the latter half of 2018 were stated to be less than 1.4% Fe203 mark as reported so not clear what has happened since.
I suspect once PLS ramps up it will address this issue in its spodumene process flow sheet, and one approach if possible would be to increase the grade of spodumene above 6% if possible, because my understanding at one point was that PLS could produce technical grade concentrate although in the lab, albeit based on what I can see in the production Anns of late it has been unable to do so IMO to date. So the question is how did it actually get to the stated Fe203 targets in its previous 'lab' Anns, where some were said to be well below 1% and are now struggling at this stage to get even to 1%. When that improves the price PLS receives IMO will improve. Its pilot work back in Feb allowed that to happen itself - see page 8 - but I am not sure the complexity of teh process it used to get to those results compared to say AVZ (and herein is alwasy teh risk in that what you do in a lab may not translate to teh field but time will tell and I suspect with some tweaking PLS will get that iron value down.)
http://www.pilbaraminerals.com.au/site/PDF/2106_0/CorporatePresentationFebruary2018
Not really much more to say here and all the above is posted IMO with a few VBs downed.
Essentially wrote a lot to say didley squat.
All IMO IMO