1) ASX listed lithium explorer Pioneer Resources (PIO) several years ago (2018?) found a relatively small amount of pollucite on one of their WA tenements. They mined and sold it all over about a year, I believe, to a US company. Subsequently, they changed their name to Essential Metals (ESS), then last year delisted after agreeing to a scheme of arrangement with ASX listed Develop Global (DVP). Not by name, but Pioneer's "Sinclair Mine" is mentioned on the second of Cesium's 2 pages in the USGS Mineral Commodity Summaries, years 2020-2024.
2) Here is the link to the United States Geological Survey's Cesium and Rubidium Statistics and Information page. It contains a brief history on the discovery of Cs and Rb, all the links from 1996 to present for the Cesium and Rubidium pages in their annual publication "Mineral Commodity Summaries," plus 5 "Special Publications" which I've never noticed before and will make time to read over the weekend. https://www.usgs.gov/centers/national-minerals-information-center/cesium-and-rubidium-statistics-and-information
3) Two years ago my daughter set up Google Alerts for me for caesium, cesium, rubidium, lepidolite and Lepidico. These 5 subjects absolutely flooded my email inbox daily with articles, academic research, company announcements and any digital publication globally which included these words. When unable to keep up (which was usually), I'd divert them to a folder, but ended up deleting the lion's share. Since around the beginning of this year, I've been saving them again and your post above has prompted me to look them over this weekend. Will report back.
4) I don't remember the publication, but read 2-3 years ago that research showed when rubidium is added to EV batteries, it extends their operating temperature range. The source might have been from the US, as I had posted something on HC at the time about hypothetically being able to drive from Alaska to Mexico. I imagine caesium would provide the same advantage, as (if I recollect correctly) BASF mention on their website lower operating temperatures can be achieved in manufacturing when using their caesium-based sulphuric acid catalyst. Again, will check this and report back.
Our 13 October 2021 announcement Caesium product development work expands offtake options in looming tight market informs:
• Caesium sulphate, carbonate and hydroxide catalyst applications lead to reduced energy consumption and higher yields, that should help offset a material proportion of Scope 3 greenhouse gas emissions
Is "reduced energy consumption" due to lower operating temperatures? Possibly this was detailed in our GHD report? Will check.
Also, is caesium/rubidium's wide temperature range why they are used in perovskite solar cells? From our 21 October 2019 announcement High Specification Caesium-Rubidium Formate Produced:
Work is ongoing to produce other caesium and rubidium compounds that have potential application in the oil and gas industry, as well as in the manufacture of perovskite-containing solar cells.
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