There wasn't any additional detail in the 31 August 2021 AIM announcement. This does however clarify that it the prevailing price of lithium products and that it is a formula.
The "s" in products tends to indicate that some sort of average is created. I don't know if that average is for different products like SC6 in different regional markets (reducing the weighting to pure Chinese pricing) or possibly across price estimates by different market information suppliers like Fastmarkets / Benchmark mineral intelligence / SMM. Given they decided not to disclose the formula at the time, it probably won't be disclosed. They are likely to have another Q&A session sometime so this may be a chance of clarification.
From 31 August 2021:
A11 Price at posting:
40.5¢ Sentiment: Buy Disclosure: Held
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