Ann: Lithium-Bearing Pegmatites Identified at Andover, page-7

The pegmatite is processed into a spodumene concentrate. Consider that the current Australian operating hard rock mines were being commissioned when spodumene was less than $1k usd per tonne… this suggests they were economic back then pre the ev boom!.. note operating costs are up considerably from then too as inputs are going up ( like acid and diesel and electricity and capex and wages). Obviously higher grade is always better.