NVA - Snow Lake Resources, page-31

That reserve is the dregs of what was left at the end of the open cut. To the point that they left a lot of it behind when they recently converted the void into a tailings storage. Note the copper credit there is worth as much as the gold so its more like ~0.9g/t Aueq.

The issue with low-grade deposits is they only work with large-tonnage operations. Which are typically expensive to develop. Even if they prove up a multi-million oz reserve and use a heap-leach approach, the only way I can see it developed is with a JV partner with very deep pockets.

Most of the big gold mines in Australia are open-cut - Boddington/Kal Superpit/Telfer etc but typically higher grade.