@CravenSpecialMild .... "
Mining the orebody at 4% is impractical. You would gut it and end up with lots of small pits."
I've been going over the information I drew up in my maps of the mineralisation and in the MRE released back on 1st July to see around about what grade we could get away with. Especially useful is the grade/tonnage curve on pg 16 of that announcement.
The curve very much flattens and eyeballing it I get around 38mt at just above 2.5%, and about 32Mt at around 3% and about 21Mt at 3.5%. The cut off grade rises the entire time with the smaller higher grade meaning many smaller pits as you have described.
Using just one larger pit around the huge
X done in the drilling is indeed higher grade and lots of thick intercepts of high grade, making something around the 2.5%-3% grade very possible with well over 20Mt just in that area.
The more I think of it the 2.5% grade starting plant makes the most sense, with easily over a decade at that level even for a larger processing plant, or possibly 20 years for a smaller 1-1.5Mt/yr plant.\
At 1.5Mt/yr, the plant could produce over 20,000t/yr of Ferro niobium for the best part of 20-25 years. That's also before we have any upgrades to the resource which will come thick and fast over the next year or 2.
Around 2.5% grade is an obvious choice as that's the grade being used at Araxa, and there is a lot of published information about these processes. I will not be surprised if we get the recovery up to around 60% at this grade either as it's what's claimed for Araxa. Because of our much lower Thorium levels, the processing should also be a little easier, or perhaps cleaner than Araxa's FeNb...
At 60% recovery, revenue becomes over $A1B/yr with around a 60/70% profit margin.
Starting with a smaller FeNb plant so that any expansion can happen with a Nb2O5 refinery and increasing demand for battery uses seems a likely possibility to me, with the Niobium Pentoxide refinery paid for by offtake agreements by 2030/31 as a fast expansion route, with cashflow from FeNb paying for our contribution to a refinery and allowance for expansion of the processing plant built in from the beginning.
(20min delay)