I would argue that price action doesn't = sentiment, but it is a...

I would argue that price action doesn't = sentiment, but it is a reflection of the prevailing sentiment. In fact, IMO it's more accurate to represent the equation the other way: sentiment=price action.
Although I have remained bullish on lithium and GXY all this year, the market as a whole has been skittish at best, driving the SP lower on fears of lower lithium prices. As the market becomes increasingly confident that the opposite is occurring, the SP will respond accordingly. Friday's action may be a reflection that sentiment is beginning to shift the other way. If not, it will in time.