peak to acquire 100% interest in ngualla rare , page-87

@Jaded: as I understand it, there might be a trace of a mineral that would be uneconomical to mine at the given concentration, if it were on its own. But if there's some other mineral that is economical to mine in the same location, it can become worthwhile to extract that trace mineral as well - the marginal cost of extracting the mineral, given that the ore is being pulled out of the ground anyway, is somewhat less than the cost of pulling the ore out of the ground.

So let's have a look at the figures from the releases on PEK's website (4th and 11th of August 2011), and cross check against a critical rare earth report summary I found with a quick google. The key "critical" rare earths are neodymium, europium, terbium, dysprosium, and yttrium (Nd, Eu, Tb, Dy, and Y) - at 16.8%, 0.3%, 0.05%, 0.09%, and 0.22% of the rare earth content in the Peak Ngualla resource, respectively. The most valuable of the "non-critical" rare earths are lanthanum and cerium (La and Ce) - which make up 27% and 48.5% of the rare earth content. Multiply these percentages by the percentage of the ore body that is actually REEs - anywhere from 1.5% to 5.83% in the PEK report I'm reading - to make up the percentage of the ore body that is the element in question.

So the Eu, Tb, Dy, and Y components are low. Probably not economical to extract in themselves. But the La, Ce, and Nd component of the ore body probably makes it well and truly economical to extract the ore, and if you're extracting and refining the ore, pulling out the Eu, Tb, Dy, and Y as part of the refining process is almost certainly worth doing. It might not be a huge amount, but it does add to the value of the resource.

There's also suggestions that the ore body contains other minerals of commercial value - specifically, phosphate, niobium, and tantalum. Peak hasn't quantified this, so commentary about the value of those minerals is highly speculative at best, but it suggests that the value of the mine might well go higher still.

DYOR, but I wouldn't dismiss a company just because the figures seem to be light on CREEs. Wood, trees, forest, etc. The JORC estimate next year will be the hard information we all want, and that's what is most likely to trigger significant moves, IMO.

Disclaimer: I am not an expert in these matters. My opinion is subject to change at any time. This comment is based upon my understanding, and could very easily be flawed. If you're relying on me to make up your mind for you, you're nuts.