That said, let's delve a bit into where you can find lithium.
Primarily granitic pegmatites - LCT type (containing lithium, cesium, and tantalum), apparently.
According to the
second paper I entered, low-temperaure country rocks through which Li-rich granitic melts intrude will result in economically significant lithium pegmatites. The basement or country rocks for the Ukrainian Shield are granite and gneiss - both of which are higher temperature rocks. So that's a strike against good lithium deposits. But then again, it's likely this material has been reworked (especially considering the age).
Mindat reports, "[Lithium pegmatites] most likely formed from
S-type granites or possibly
I-type granites, with a higher aluminium content (
peraluminous granites)."
This paper indicates the presence of S-type granites in the Ukrainian Shield.
Looking at the original map I showed with the original paper I mentioned, sites 8, 9, and 11 show lithium as per that paper.
