In response to yourselves:
For those that are busy and want a short (non VB driven rant) versionI do not believe a standalone tin/tantulum mine is viable at Manono. Tin/tantulum viability IMO is only through extracting them as credits in the production of 6% grade spodumene in the process flow sheet, and fundamentally using them as credits to offset transport costs.
For those that want the detailTin (and tantulum) here will be used as a credit for transport costs for producing and selling 6% grade spodumene IMO. The spodumene process flowsheet will deal with the tin and tantulum credits through magnetic separation IMO. I dealt with this issue some time ago in the embedded posts within this post, Post #:
37459627, so up to yourselves to read them if you want to.
Whilst I recognise in the past the Manono deposit itself had a standalone tin mine, my view is that the grades these days may be too low to foster a standaone tin mine operation there that is not recovering the lithium is the assumption. But the point is cut off grades for viability are difficult to estimate for a stand-alone tin mine here IMO, given the size and depth of the resource alone compared to other standalone tin deposits that do not have significant depth of resource like AVZ, which means AVZ would have a better waste to ore ratio in its development btw.
Now, in the link below, for prospective tin mines they are estimating cut off grades of 0.3% open cut and 0.7% underground mining for viability, and to this end the AVZ tin grades just less than 0.1% (so on that basis a stand alone tin mine for AVZ might be marginal at best IMO). See slide 8 in this link,
http://www.kasbahresources.com/site/PDF/1256_0/AfricaDownUnderConferencePresentation - with the viability numbers based on by the looks of it US$16,000 per tonne for tin at the time of the presentation -
http://www.infomine.com/investment/metal-prices/tin/5-year/ (note 2204 pounds in a tonne). With tin prices now above US$20,000 per tonne cut off grades will be slightly reduced from those in slide 8 above btw.
The paragraph in the following link is also interesting -
http://www.ga.gov.au/data-pubs/data-and-publications-search/publications/aimr/tin:
"
At Greenbushes mine, in southwest WA, production of tin ceased in 2007 with the closure of the smelter. Tin resources for Greenbushes operations have not been publicly reported for more than a decade. Historical estimates of tin resources for Greenbushes have not been included in Australia's EDR since 2008. Global Advanced Metals (GAM) indicates that it has produced by-product tin from its tantalum deposit at Wodgina about 100 km southeast of Port Hedland, although amounts are not reported. Production at Wodgina resumed in April 2011 with ore processed at GAM's Greenbushes facilities. Wodgina closed again early 2012 following softening of demand for tantalum."
I also however do recognise that the tin grade at Greenbushes is lower than AVZ (but Greenbushes has a higher tantulum grade btw) as evidenced by the italic below on page 1 of the following link -
http://www.kenex.co.nz/documents/papers/AOD%20Monography%202018%20Greenbushes.pdf:
"Current resources for lithium, which is the only commodity currently mined from the Greenbushes pegmatite, is summarised in Table 1. Tantalum and tin are recovered as by-products during lithium processing, with the tantalum grade averaging 127 ppm Ta and tin grade averaging 199 ppm Sn. Both tin and tantalum resources remain, particularly in the albite zones of the pegmatite, but these have not been estimated since the mining operations for these commodities were placed in care and maintenance in 2005."
For reference, AVZ's maiden resource had a tin grade of 844 PPM and tantulum grade of 43 PPM. (Note 10,000 PPM = 1%). Refer post: Post #:
34683622Which takes me to the point of rabbiting on herein. If a standalone tin mine is viable here, meaning you develop separate pits, one for producing spodumene and one for producing tin, I suspect for a tin mine to be viable here you would need to produce a concentrate that has tin/tantulum and possibly niobium in that concentrate and/or have a process flow sheet that recovers all three separately. But the more likely scenario given the tin/tantulum grades, is through recovering tin/tantulum (from recollection there is niobium in the deposit as reported in the historical archives here, but not clear in my own head given the niobium grade whether it is viable to recover and the fact AVZ don't talk about niobium suggests it is not) as a credit for spodumene production through installing magnetic separators in the process flowsheet.
In any event the $ here are essentially in the lithium as against a standalone tin mine IMO btw so it is a theoretical debate in these posts btw we are having IMO.
So that has been my focus of understanding the deposit viability wise - seeking in working out the value of the tin/tantulum credits to reduce transport costs in the production of spodumene, noting I tend to use a credit of US$50 to US$80 per tonne in transport costs for tin/tantulum, whereas from recollection PLS used just over US$80 per tonne for tantalite alone in their DFS). ((( (In terms of my niobium comment above, I haven't seen AVZ report it in the assays but this is an old post from poster Mineralised done way way back which jolted my memory - Post #:
23616960. The bit of interest is near the bottom in that post - in french but there is a Table - but the key is the Nb2O5 quoted in ppm (divide by 10000 to get to %) and that symbol is niobium but it has been shortened at times in assays to just Nb))))).
Which now takes me to the incremental capex cost in a spodumene process for extracting tin/tantulum. I note the BGS capex cost for its facility is 2 mtpa facility is some US$166 million, see Post #:
34124085 - whilst the PLS capex cost for a 2mtpa ore feed facility (including a tantalite extraction stage in its process flow sheet) is A$214 million (or roughly US$160 million at exchange rate assumption) - Post #:
19271690. I suspect using these two numbers, probably looking at a US$200 - US$220 million capex cost here for AVZ for a 2mtpa facility (including the recovery of tin/tantulum as credits) in the AVZ process flow sheet (and in my modelling of the other day I use US$220 million). The other interesting aspect of the BGS PFS is the 3.5:1 tonnes waste to ore ratio (given the BGS resource) is quite high and this results in a 70% recovery assumption (7 percentage points lower than PLS), whilst I suspect given the denseness of the AVZ pegmatites and little 'junk' spaces in the ore body (given it is all pegmatite) it will give a higher recovery rate (80%) and a much lower waste to ore ratio - a cost saving.
The better waste to ore ratio and higher grade AVZ has is why I say that AVZ will get an additional 20% more spodumene revenue for each tonne of feed ore, all other things been equal at the minesite, than PLS, with AVZ also having lower cost structures at the minesite. For avoidance of doubt transport is a post mine site cost hence why in the past I have said feasibility for AVZ is all about transport costs and timing to market. Refer post: Post #:
34698690 and more recently Post #:
37646469 And to repeat a comment I made the other day, the capex cost estimates herein (and what AVZ use) essentially assume that post minesite transport scenarios and their costs will be undertaken by others (like the Chinese in their drive to develop the DRC more generally) so if AVZ is required to contribute capex to transport solutions outside its mining area it will reduce NPV and IRR in project evaluations, but the quid pro quo is also that AVZ's timing to market is also in part dependent on othrs providing it a transport solution. It is why I suspect if production commences 2021/22 AVZ
might use an alternate transport route in the short term until the more desirable transport route is developed - i.e. this assumes the most appropriate transport route might not be in play by 2021/22 so that is in effect the watch this space in AVZ's PFS to look for IMO etc etc etc)
As I said I suspect a tin/tantulum
standalone mine here is marginal, so what makes their recovery viable is having an incremental capex cost in a spodumene process flow sheet to aid recovery of tin/tantulum as an offset to transport costs IMO IMO.
If others have a different view please advise. All here to share information and to rant whilst drinking VB.
All IMO IMO IMO
