Could have been the Co price that made it uneconomical maybe....

Could have been the Co price that made it uneconomical maybe. Lithium batteries weren't exactly the hot topic at that stage.
They also used an autoclave which slows things down.
(I mixed up their output, 12t through/day rather than 12t of battery material)

Without leading towards other shares;
COB is due to be doing their PFS around the same time as Celsius is doing their SS, so that will definitely be one to compare in a few weeks.
CLQ is also planning on their DFS this month, latterite, but still, always compare.

Shows how the mines are trying to value add where possible (though CLQ is more of a tech company with a mine and various products, could make it hard for an accurate comparison of Co alone).