Well, all I know is that DEG (or, precisely, the vendor of the Blue Moon EL) has shown Au nuggets on quartz in altered **bro of the Millindinna. SEG has reported nuggets on quartz from "conglomerates" and also, from the very vague locations given on their maps, from proximity to the Millindinna.
PIO's ground covers areas of the Mallina basin sediments which are prospective for Au in the basement, both in the Cleaverville (older than the Mallina and Millindinna) and the Mallina Basin and Millindinna **bros.
**bro (or dolerite, which is **bro with a finer grain size) is a known host for lode Au in the Eastern Goldfields. usually there, the **bros lie within basalts. Here, they are within sediments. Fe-rich **bros are generally the best. This is true of the Millindinna **bros, which (from Aster data collected regionally) are Fe-rich.
So, the play is nothing special. in fact, it's the oldest play in the geology book: find a mineralised structure, chase it into a Fe **bro, and nuggets.
I have not looked particularly hard at PIO's ground for this kind of structural target. It's not too hard for people to do this kind of exercise.
