Ann: Spodumene identified at Trigg Hill, page-287

To my understanding, Rubidium is linked to Lepidolite (approx 0.3% to 3.5% in Lepidolite).
Though there have been a few interesting factors. This is an LCT Pegmitite (lithium tantalum caelsium) which is a sub set of granitic pegmatite.

To my understanding, LCT Pegmatite will give us Lepidolite, Spodumene, or Petalite. It depends on how this section has settled over time and how much 'purification' the pegmatite has gone through to give us the higher grade lithium in Spodumene or Petalite.

I have some confidence in the announcement of this thread. They have done some processes that are not just 'basic' visuals. Here is an example of XRD results for spodumene from a different project of another company.
Compositional XRD patterns of pegmatite–spodumene ore sample 1A from... | Download Scientific Diagram (researchgate.net).
There is spodumene in the ground. The real question is how much is located.

I am not a Geologist, DYOR. I do not even think I understand Geology, I just read up on what their announcement says and try to understand it.
Please correct me if I am wrong.