"Koppamurra seems to be a sedimentary deposit that has formed...

"Koppamurra seems to be a sedimentary deposit that has formed through the concentration mechanism of the rising and falling water table above a limestone basement, over a million years or more."

Their testwork is suggesting leach operation at pH 1, given all their results on met composites have been at pH 1. At this level, substiantial loss of acid will be observed due to reaction with any Ca,Mg,K or Na carbonate, oxides or hydroxides if present (noting limestone is calcium carbonate). They noted that ANSTO were working on acid consumption back in their 4/04/2022 met result announcement, which aligns with the limestone basement mentioned above:

"During testing, it was confirmed that the natural alkalinity of the mineral samples consumes acid needed for pH adjustment and REE extraction. Upstream mineral processing techniques are being evaluated to reduce the volume of acid consuming gangue minerals prior to metallurgical processing. The resultant decrease in acid consumption will support efforts to optimise the process flowsheet"

Now, for comparison, IXR released their acid consumption rate all the way back in 5/8/2020 met results, averaging 14 kg/t acid at pH 1. "Analysis of final liquors indicated an average acid consumption of 14 kg per tonne of dry ore tested."

Why has AR3 still not released their acid consumption rates over a year after their met testwork where they appear to have got indicative rates already worked out per their commentary? Until they release this very important number to estimate OPEX for processing, there is way too much unknowns as to whether this project is economic or not. So it's a no from me dawg.