I said I wouldn't post here, but decided I will give you some research I have done myself. A lot of people don't realise a lot of exploration has been done in and around various areas of WA for a long time - you just need to know where to look so I decided I'll have a bit of a look around.
If you go t page 35 of this doc for example, written in 1980, they talk about lithum and some of teh resources that are currently now in production.
https://library.dbca.wa.gov.au/static/FullTextFiles/007648.pdf
Which takes me to this point. Don't know how you will react but I was reading this Ann, and my interest tweaked when I read this paragraph. But my own thoughts is where the current drills are may be completely irrelevant to the historical data, but ultimately as I posted before all this speculation can simply go away by LTR reporting full assays. Anyway, as I keep saying there is ample room for a number of greenfields deposits but this post is provided also to give people an understanding of gangue as well.
Context
I found this paragraph interesting in one of the Anns - linked. "Mineralisation remains open at depth and to the north-west, with Liontown speculating the results indicate the shallow-dipping Kathleen’s Corner pegmatites are merging with the Mt Mann pegmatites at depth." https://www.ltresources.com.au/sites/default/files/news_file/liontown-resources-unearths-another-record-thick-high.pdf
And then this one in https://www.ltresources.com.au/sites/default/files/asx-announcements/6917464.pdf
"The mining operations will overlap with existing land users including the Yakabindie Pastoral Lease and the Native Title holders. The Company has engaged with both parties to facilitate future operations."
Why well these guys provided a summation of research/previous drills data on pegamtites back in 2007, https://trove.nla.gov.au/work/34488159?q&versionId=42668827, but unfortunately I can't access the book itself, but an organisation called mindat.org has summarised findings in that book - look at references at the bottom of each of the following, but doesn't mean they summarised them well either (and they may not relate to any of the existing cores, but if LTR if your current drilling area is expected to merge into Mt Mann well you can decide what it means, but having said that differnt cooling processes and I presume more than one geological event doesn't mean the pegamtites will be the same, and on that basis you need to continue to trust the existing Anns and comments by management on this issue. What the below suggests is probably not all teh pegmatites are good by the looks of it, so select and mine the best one *and I suspect that is where current drilling is going on).
This is what mindat.org has stated about the pegmaites studied there at that time and summarised in that 2007 book, obviously a lot more drilling has taken place, but on the data they have published they do make a lot of statements around lepidolite in the pegmatites they had studied in the area (noting the study might not be on where they are drilling at the moment (i.e. not sure) but Mt Mann they certainly talk about 'abundant' lepidolite in the pegmatite itself.
Mt Mann: https://www.mindat.org/loc-249018.html
"Is part of the Kathleen Valley group of pegmatites, centred on the abandoned gold and copper town of Kathleen. A fence and locked gate may prevent access. 5.5 kilometres north north-east of the Yakabindie homestead. The pegmatite forms a tor-like outcrop, straddling the northern spur of Mt Mann. The pegamtite is 400 metres long, up to 7 metres wide, intruding the Kathleen Valley **bro complex. It contains abundant lepidolite as scaly masses associated with albite, and abundant coarse bladed white spodumene crystals. Andalusite, corundum and pale brown dravite has been reported from a small pegmatite just east of the Mt Mann pegmatite."
Jones Creek pegmatite: https://www.mindat.org/loc-249019.html
"Part of the Kathleen Valley group of pegmatites centred around the abandoned gold and copper town of Kathleen. A fence and locked gate may prevent access. The location is a swarm of pegmatites. The pegmatites are spodumene rich, as bladed white crystals to 30 cms long by 2cm wide embedded in quartz and coarsely crystalline feldspar, with locally coarse muscovite. The spodumene fluoresces orange in long wave ultraviolet light. Lepidolite is minor at the pegmatite. A small shaft has been sunk next to the pegmatites for copper but is genetically unrelated to the pegmatites. The copper ore was malachite and chrysocolla."
Main Road tin pegmatite (Kathleen pegmatite; MC34 pegmatite) - https://www.mindat.org/loc-249017.html
"3 kilometres north-east of the Yakabindie homestead. Part of the Kathleen Valley group of pegmatites, surrounding the abandoned gold and copper town of Kathleen. Access may be blocked by a fence and locked gate. Nearby to the pegmatite is the Main Road gold mine open pit abandoned in the 1980's. The pegmatite has intruded the Archaean Mount Goode tholeiitic metabasalt, and is a lithium rich pegmatite, 200 metres long by 5 metres wide, striking north-west and dipping to the south-west. The pegamtite consists predominantly of albite and lepidolite and lesser quartz and muscovite. Lepidolite is found as fine grained deep purple masses to 40 cms and wine-red crystals to 20mm. Cassiterite is abundant as black patches to 30mm associated with lepidolite and albite, and as euhedral crystals to 5mm in tiny miarolitic cavities. Abundant pale to deep green damourite occurs and comb-like masses of cleavelandite. Cassiterite was mined here between 1945-1953. The site is marked by a large area of white pegmatite float and blasted material."
Comments on other pegmatites in the area are here:
https://www.mindat.org/loc-302405.html
https://www.mindat.org/loc-302406.html
https://www.mindat.org/loc-302408.html
https://www.mindat.org/loc-302409.html
Obviously, where LTR is drilling could be lepidolite free but full assays will determine that, but METs should also be able to tell the story and story as per the December PFS is the mica can be dealt with (and obviously teh cost estimates provided by LTR in that PFS are based on that basis).
The simple search I did is herein:
https://www.google.com/search?client=firefox-b-d&ei=R3ZeXp-OGcfnz7sPqfC-6Ao&q=Yakabindie+Pastoral+Lease+pegamtites+spodumene+and+lepidolite&oq=Yakabindie+Pastoral+Lease+pegamtites+spodumene+and+lepidolite&gs_l=psy-ab.3...8805.12021..12563...0.0..0.338.4066.2-15j1......0....1..gws-wiz.pec15x4DCxA&ved=0ahUKEwjfzayCzv7nAhXH83MBHSm4D60Q4dUDCAo&uact=5
The importance of removing Gangue
The amount of and type gangue, and varibaility of it within the ore body itself, can impact recovery rates and what emerges from your initial cushing and screening stage after magnetic separation for example, before been fed into the more complex parts of the flowsheet, and if not removed to required specs it impacts the process flow sheet itself. In other words, the pegamatite to gangue ratios/percentages impacts separation of ore from gangue in the process flowsheet in the initial stages itself and how the 'recovery of the minerals' responses to that process differs depending on teh extent of gangue, for example.
If you have a homogenenous thick deposit IMO you can better deal with the issue than if you don't - certainly at depth the pegmatite looks thick and high grade.
https://en.wikipedia.org/wiki/Gangue
https://www.merriam-webster.com/dictionary/gangue
https://en.wikipedia.org/wiki/Friability
By way of background, when you say an ore body that your using that feeds into the plant grades 1.6% Li20, what you are saying is 20% of that ore is spodumene - to understand this, go to Table 2 of this link where this entity says its pegmatite has 13.8% spodumene: whilst the grade of spodumene was around 1.09% Li20 (noting 100% spodumene occurs at 8.03% spodumene (some slight rounding errors here etc etc) - https://www.asx.com.au/asxpdf/20190801/pdf/4473vblh92dfz7.pdf .
Or this comment here - https://leadingedgematerials.com/lithium/:
"According to UBS, Australia is a significant player in lithium production, hosting some of the world’s largest and highest-grade lithium hard rock spodumene deposits. The mineralised rock typically contains 12-20% spodumene, approximately 1.0% to 1.5% lithium oxide (Li2O)."
If the deposit grades 8.03% Li20, that area is100% spodumene - https://www.sgs.com/~/media/Global/Documents/Flyers%20and%20Leaflets/SGS-MIN-WA109-Hard-Rock-Lithium-Processing-EN-11.pdf
3.1% Li20 suggests, which seems to be the go in the lates drilling suggests 40% of the ore is spodumene, so there is a lot less gangue to deal with, so he question is how easily is it liberated from the gangue. If easy, 'bob's your uncle' outcome IMO, so suspect the METs will be fine as well. Just a guess, but speculation won't go away until the full assyas are known, despiteteh METs obviously been able to deal with the deleterious elements by the looks of it.
If it is homogeneous/consistent rock it can be dealt with in the processing/ore feed facility. If that rock has a lot of gangue/crap around/embedded within it, it can effect recovery and quality produced. the rest of the pegmatite is generally quartz, feldspar and mica.
If the spodumene cannot be liberated then you need to use floatation. Floatation is the only place you can remove deleterious elements because teh ball mill the 'ore' to P80 of 106 microns. DMS is a liberation stage only and so for ore to be DMS ready it has to be large coarse grains, easily liberated, with low deleterious elements. If it fails any of these then DMS is not an option and you move to ball milling and the floatation circuit etc etc I posted something onthis aspect in the AVZ thread but very relevant to al lithium depsoits
Post #: 43092083
Finally as I keep harping on, the world needs more than 1 greenfields lithium project.
And whilst teh above is interesting, it is obvious not all pegmatites are the same in coarse grain sizes, deleterious elements and grade. It is is obvious too me where LTR is mining, there view must be that is teh best targets because they have the best grades and lowest deleterious elements, which can be dealt with in a METs framework - as per the SS work I suspect. I guess full assays and METs for the drills undertaken since the last METs on these new drill results should confirm that to.
All IMO
(20min delay)