To increase transparency, Fastmarkets has further clarified how it handles price movements during periods of low liquidity.
Factors that Fastmarkets may consider during times of low liquidity include, but are not limited to: market fundamentals such as changes in inventory levels, shipments, operating rates and export volumes; relative fundamentals of similar commodities in the same region; relative values of the same commodity in different regions; and changes in the value of the commodity’s primary feedstock(s) or primary derived product(s).
You can find the updated methodology for global lithium assessments here: https://www.fastmarkets.com/methodology/metals/lithium.