This whole arena of mineral sands, heavy minerals and REE gets...

This whole arena of mineral sands, heavy minerals and REE gets complicated.
Heavy minerals (as distinct from heavy metals) typically refers to Zircon, Rutile and Ilmenite. These minerals do not contain REEs to any degree, if at all but have had industrial applications for decades,and have been produced by companies like ALU.ASX.

REE is a whole suite of elements that fall under different categories and are found to be prevalent in a range of minerals:
-light metals used in magnets - principally Neodymium and Praseodymium
-heavy metals used in magnets - Dysprosium and Terbium
-other metals, whether heavy or light, with varying industrial applications and value: Cerium, Erbium, Europium, Gadallinium, Hafnium, Holbium, Lanthanum, Tantalum, Samarium, Tellurium, Yttrium, Yterbium,
Sometimes Scandium is associated with REE minerals but it is not categorised as a REE. It is nevertheless a less commonly available element that is also categorised as a critical element these days.

Titanium, niobium, and tantalum are sometimes categorised as rare earths but generally are excluded from this classification these days.

REEs occur in various minerals (ores). The ones that are mostly mined for the extraction of REEs are: monazite, bastnäsite, xenotime, zircon. These minerals are typically found within a class of alkaline ores called carbonatite. Mountain Pass in California and PEK.ASX are examples of bastnäsite /carbonatite while LYC.ASX mines monazite at Mt Weld.

Another aspect needed to demystify Rare Earth Elements, is that they are not "rare" at all (at least compared to gold, platinum etc) in terms of their occurrence within the Earth's crust. Their "rarity" arises from the difficulty of separating the individual elements within the ore, so as to produce "pure" substances.

Hence, the aim of AHK to produce a rare earth mineral concentrate (REMC) that contains all the rare earths from the ore for sale to refineries (mostly Chinese at this point in time, but also Lynas now, with ILU, ASM, and others going forward).

AHK will concentrate the REE and heavy minerals within the sands at Sandy Mitchell, and send it to Currumbin Minerals in Queensland for further processing into a Mixed Rare Earth Concentrate (MREC) (and separate the other heavy minerals?) under a toll processing arrangement that AHK then sells to other parties who can turn the MREC into Mixed Rare Earth Oxides (MREO), that yet others can separate particular REEs from, normally as oxides of specific REE metals.

Metal refineries then take the oxides and create pure metals in various forms (eg ASM's Korean Metal Plant)

Another element that is often mined by mining companies is Hopium. This is the element outside of the Periodic Table that is most valued by resource companies of all types.