Understand what you are saying and agree with what you said around cut off grades, but I define homogeneous a little differently.
I suspect the pegamtite system AVZ has at Roche is formed by one geological event - Refer Post #:
32169820. It was also something I posted about when the subject of nearology cam up with 4CE - Post #:
32170723. When you have one thick pegmatite and it goes to depth the theory as to why it is homogeneous is that it has been formed by one geological event and the pegmatite itself has had uniform or close to uniform cooling so that its specs, particularly in its crystalisation structures, are not that different within the pegmatite itself (especially as it relates to composition). Li20 content can vary within the pegmatite but composition is similar/uniform in a homogeneous pegamatite giving an element of predictability to how you deal with it within a mining process flow sheet. I suspect Greenbushes is similar and whilst at depth it would appear LTR has an element of homogeneity within it too.
Now where you have thin pegmatates that are dispersed or are in between layers of overburden, assuming the event comes from the same magma chamber the cooling process can be different which then plays with the chemical composition and uniformity of each pegamatite. The situation would be worse IMO if the pegmatites are formed by differing geological events. Reading the geological reports of some of the players it is unclear too me exactly the uniformity/similarity/composition of their pegmatite systems themselves and that I think can become an issue in a process flowsheet, if not properly planned.
One thing for sure, the lower than expected recovery rates from the likes of PLS, and now need for new capex spend, is going to be a huge learning curve for any player entering the lithium market. And I am sure they will test test test to ensure that whatever process flowsheet they put in place can be amenable (at low cost) when and if the pegmatites the spodumene is sourced from is different in composition (and by that I mean where there are some stark differences).
Anyway in terms of AVZ higher grade means you need to treat less ore to get to 6% grade concentrate, which by definition because you are treating less ore then means you have less deleterious elements to remove. As per post: Post #:
39721929 and Post #:
39722917IMO it has always been about a viable transport route here and whether the market can absorb any production arising from AVZ (and that means demand must be greater than supply for AVZ to have a chance to enter the market, specifically providing spodumene concentrate to the hydroxide market).
All IMO IMO IMO
