I had a re-read, and some things leapt out at me;no drilling off...

I had a re-read, and some things leapt out at me;

• no drilling off tracks, which means no heritage surveys were undertaken, so there's no understanding which parts of the mineralisation are not extractable due to being within culturally sensitive areas
• no surveying of holes was undertaken. Guess it's too expensive to pay a surveyor to drive out there and do a DGPS survey
• Metallurgically wise, the tests were undertaken at 100g/L r whatever HCl or H2SO4. Sure, sure, this is a lot. Theres whatever acid consumption in kg/t of ore, as everyone else mentioned/ But the key thing other people haven't picked up on is these tests are at 2% pulp volume. So you have 100g of HCl and 20g of clay, or a 5:1 acid:clay ratio. This is a lot of excess acid, and a lot of water.

One way to get a reaction to happen is to provide an excess of the key reagent, to drive the reaction to completion. In this case, I question the reality of a 500% stoichiometry of acid to clay. I guess the acid isn't consumed and the clay can be sucked out and the PLS re-used, but if you need to remove the dissolved REE's you can't neutralise 10% HCl because you need to add a base, and your dosage of base (likely NaCO3 or CaCO3) would be 100-400% the weight of the ore in order to raise the pH enough to get the pH from 1-2 to 3-5 to drop MREC out.
Think about that. This is 300Mt of clay, you need 6,000Mt of water, and 300Mt-1500Mt of Na/Ca carbonate, plus the acid. And you get whatever you get.
As we all know, Australia is drowning in fresh water.

I really think this is a complete furphy until they can do the metallurgy to show higher pulp volumes, realistic acid dosage, and demonstrate a method of dropping MREC out.