Ann: High-Grade Rare Earth & Niobium Zones at C3 & C5 - Mangaroon, page-104

Good stuff salpetie and 2ic, thank you both for the ongoing analysis and discussion.

Putting my own bias and vested interest aside, the DRE exploration Co vs Mangaroon REE’s is a great case study to look at the interplay between early-stage exploration scenarios vs the nitty gritty detail at the individual project level…and the longer we go down the road pursuing the REE’s the more weight needs to be assigned to those project level specifics.

As a general observation, I notice some commentary (not 2ic/salpetie etc) that focus on the literal interpretation of DT’s commentary around the “world class nature” particularly in regard to the NdPr:TREO ratios or initial recoveries etc. I get that, from a company perspective it makes sense to promote the positive aspects and potential for a given project….and its then largely up to everyone else to put that into context, however you see fit.
The NdPr:TREO values at Yin (and Yangi for that matter) are indeed high relative to peers, but this in isolation is somewhat meaningless, without first considering the percent TREO…this is something that 2ic shows via multiple detailed workflows... if people take the time to go through them.
The reason %TREO is crucial as a starting point (at least in my mind) is because that is what will inform and underpin how a deposit may be economically mined and processed. Sure, the NdPr:TREO ratio is also important (as are many other factors), but its secondary.
I.e. you will be mining based primarily on the %TREO and then scheduling/blending/batching etc based on various domains of which NdPr:TREO ratio might be one…..but not the other way around.
So ultimately it comes down to the question of what is better:
XMt @ ~0.93% TREO with 37% NdPr:TREO
Or,
XMt @ ~8% TREO with 23% NdPr:TREO

and there can be multiple answers depending on viewpoints and objectives…but simplistically speaking and all else being equal I think most would agree that the 8%TREO with a slightly lower NdPr:TREO ratio wins.
So when you see HAS and DRE to some extent focusing on the average NdPr:TREO...it pays to keep it in perspective:


Anyway, that aside, in many presentations and webinars DT has referenced the C3-C5 drilling pattern as being designed to target a “Mountain Pass” style system…. now to be fair this is more in terms of extent rather than grade/tonnage etc with the acknowledgment that these small-ish but high-grade systems can have a relatively small footprint.
So, given it gets mentioned frequently (including the last announcement) its useful to at least consider it. The comparison below shows the plan view of C1-C5 relative to Mountain Pass at the same scale. The blue zone labelled Sulphide Queen is the important area, that's essentially the main carbonatite that hosts the REE mineralisation.


If we then zoom in and look at the actual footprint of the main REE mineralisation within the Sulphide Queen Carbonatite, where the currently defined zone of rare earth mineralisation covers a strike length of approx. 840m and the true thickness of the >2.0% TREO zone ranges between 5 to 80m:

Of course the 'mineralisation' could be any number of geometries, but the less blob-like things become the more difficult and less attractive they become (for many reasons). So, this is where it becomes speculative depending on how blue-sky you decide to view it....I would say that technically speaking yes its still possible that there remains a high-grade 'Sulphide-Queen' sized deposit (at least footprint) system hiding towards the southern end of C3-C5…..but it is starting to look improbable (just imo).
The other point is Sulfide Queen is ~8% TREO which comes back to the initial points. The principal economic mineral being Bastnäsite (carbonate) with typical REO of ~75% compared to C1-C5 being Monazite (phosphate) with typical REO of ~65%....so already there is more TREO per unit volume

I wonder if maybe the size of these particular carbonatites at C1-C5 has meant that there just hasn't been a suitable point of focus for the REE-bearing fluids, and so the end result is just broad zones of lower grade mineralisation compared to say Mountain Pass/Sulphide Queen where all the mineralising fluids have preferentially focused into a relatively small area.

Anyway, just thoughts...as always dyor.
GLAH