you need a good econ geologist. If I was running your prospect, Id be looking at the Hydrothermal and ground water. Ill bet youd see a nice recovery with some really simple means.
Your pegmatites should be more enriched in spod and lepidolite (see if they used a term "perthite Spodumene) and associated Li/Sr feldspars. See any masses of pink in the spoil piles? We gotta carefully use all our senses because the best stuff may be missed by random sample means.
Whats the market for Li this week?