Hi Mckhenry,
Great questions.
The EIS co-funding was announced in December last year and is similar to other EIS grants. 50% of the drilling costs are covered by the grant from the state government, in this case for up to $180k. The grant is paid upon completion of drilling, and then delivery of any drilling material to the GSWA (if diamond core) and then the final report. It is a great program that supports exploration within WA and we currently have funding for Tiger and the Gifford Creek Carbonatite at Mangaroon, and previously had support for deep drilling at Orion and Yin amongst others.
Like rare earths, economic minerals of niobium are resistant to weathering. They tend to accumulate in areas of deeper weathering (as the carbonatite weathers away). This also tends to have the added benefit of improving metallurgical recoveries. This is why many mines hosted within carbonatites are in the weathered zone such as Mt Weld, Araxa, Nguala etc.
Why we can’t detect accumulations of these minerals directly, we can potentially detect areas of deeper weathering with techniques such as gravity (weathered rocks have a lower density than fresh rocks) and electromagnetics (weathered clays tend to have a different resistivity and conductivity compared to fresh rocks). We can then target these areas of possible deeper weathering within the carbonatite in search of thicker and higher grade mineralisation.
In regards to grades and tonnages that may become economic (metallurgy being a major contributor to that as well) we can look at the three currently producing niobium mines globally. The biggest and highest grade is Araxa in Brazil with over 460Mt @ ~2.5% Nb2O5 in reserves (the resource is unofficially reported to be well over a billion tons at 1.5%). The other two Niobex in Canada which is an underground mine is 698Mt @ 0.41% Nb2O5 and Catalao in Brasil has 1.7Mt @ 0.8% Nb2O5 in oxide, 40Mt @ 1% in fresh rock and 6.5Mt @ 1.2% Nb2O5 in underground resource.
From that we see quite a range from ~40Mt – 800Mt and from 0.4% to 2.5%.
Again, metallurgical recovery will play a large role in economics and geos a fair way to explain the wide range of resource grades.
A nice overview of Nb can be found here.
(20min delay)