Things that make me go Mmmmmm

Found time to look a little deeper into the SS and verify that the sausage matches the sizzle. Great run up with a very promotional board, met work breakthroughs, very large MRE tonnages as you expect from igneous intrusions, well timed CR and in the US where home of the free market has become home of free money...

Unreasonable peer comparisons are somewhat par for the course these days, where companies choose the metric that flatters for their bubble charts or tables. However, when it crosses the line into ridiculous deceptive spin I begin to worry if that is a style and strategy used across all releases for the project (ie if you see one cockroach, be worried how many are hiding behind the walls). Exhibit 1 was a red flag prior to the SS but is worth noting for a sense of style


I'm at a loss to think of a conventional hard rock deposit with ~6% TREO grade except for Mountain Pass, one of the top few hard rock deposits globally (not that ARR included MP in their peer comp tables). Mountain pass ore grade is ~6% TREO but upgrades through the beneficiation plant to 60% TREO, where Hallack Creek upgrades from ~0.4% to ~4% TREO through the beneficiation plant. Basically, ARR is trying to pass off HCk ore concentrate (the stuff that goes to leaching) as a direct comparison to ore in the pit (pre-concentration) of other hard rock deposits... complete BS, unnecessary and only serves to make one go mmmmm.

Beyond the reality of grades per and post concentration, it all comes down to metallurgical recovery to drive operating margins and costs relative to peer development competitors. I like the gravity, DMS and WHIMS simplicity, scalability and low-cost part of the plan, and still early days, but just running my eyes over the SS flowsheet and Met Section I find this whopper of a contradiction... The last and largest 300kg test of continuous WHIMS operation by Wood from 500micron P80 grind showed horribly low recoveries to final concentrate of 39% vs exactly double that recovery assumed in the SS based on earlier batch work 78% recovery (which includes losses in crushing stage) ... Mmmmmmm






As others have noted, ARR were very happy to reject actual test leach recovery for DyTb and other and accept the metallurgist "opining" (rhymes with whining) that low DyTb recoveries were due to low concentration and erroneous test results. It's possible, but I'm troubled by the fact heavy often have lower recoveries to leach than lights, depending on the many different ore types and leaching agents/conditions. An example is provided in the 2023 paper on the HCk ore titled Mechanism and kinetic study of rare earth extraction from allanite by direct acid leaching...

Mechanism and kinetic study of rare earth extraction from allanite by direct acid leaching - ScienceDirect

While the consultant met might hand out hope that recoveries of heavies may improve with larger pilot plant testing, it makes me go Mmmmm, and seems a high-risk leap of faith to hang the study on. To be fair they have flagged this risk, and tabled very low Yttrium recoveries, which is the heaviest RE and often used as a proxy for HREE analysis... btw, Yttrium is 221ppm in the MRE and Praseodymium is 189ppm so I can't see the excuse that very low Y2O3 levels in the batch test was the cause of very low Y2O3 recoveries??


All these cockroaches hiding in the walls doesn;t make me confident of what other numbers have been 'optimistically' placed into the SS to make it sizzle? Back to the 4% con grade vs 60% con grade for monazite con feed, I agree that H2SO4 leach at 90deg is better than acid bake at 600deg and higher acid concentrations, but there is also the sheer tonnage difference to consider. HCk needs to leach ~15 times more concentrate than a 60% TREO monazite con, which at 250kg H2SO4/tonne of feed is a sheetload more tonnes and acid consumption (15x bigger plant, 15x more leach liquor to process etc)... I'm not sure 250,000t of 4% TREO feed into lower temp leaching tanks is going to be much cheaper than 17,000t of 60% TREO into acid bake/leach arrangement (especially considering HCk still needs to roast that 250kt con at 600deg to calcine the leach feed so the Ce will drop out).

I've seen enough to make me very wary of exactly what the final metrics will be for Halleck Ck, and red flags that support my gut feel that the SS opex just looks to low at ~US$100M annual. That is a hell of a large leaching plant and separation facility with proportionally high reagent costs etc. A lot of time and work to be done before ARR can actually produce anything close to bankable. Will be an interesting one to follow and see if these optimistic projections play out or fall over under the weight of factual analysis. Too much slick and dodgy stuff going on for me to be confident this isn;t high risk of the latter... I'll be watching from the sidelines as a non-holder.

GLTAH