That spike to 30c on auction has been mentioned a couple of times, due to 34m @30c (two single buy orders) placed by an US ETF Fund, VanEck Vectors Rare Earth on that day.
Up to 26 March 2018, The US ETF Fund bought 10.5m more AVZ shares as published on their official website.
VanEck Vectors Rare Earth/Strategic Metals ETF currently only hold four ASX lithium stocks:
ORE (Market cap: $1.5b) - Hold 2.3m shares, worthy US$10.7m;
PLS (Market cap: $1.4b) - Hold 16.2m shares, worthy US$10.9m;
GXY (Market cap: $1.3b) - Hold 4.6m shares, worthy US$11.4m;
AVZ (Market cap: $0.5b) - Hold 45.5m shares, worthy US$8.9m.