Did Rio Tinto Just Launch A Secret Rush For This Metal?Interesting article from a couple years ago re their MinnesotaTamarack deposit joint venture with Talon Metals. The deposit has some cobalt, as described ...
Tamarack also holds cobalt — at an overall grade of around 0.05%. The size and grade of this deposit is a little skinny for a major like Rio Tinto (cobalt deposits in the DR Congo, by comparison, grade around 0.5%). Prompting the company to joint-venture Tamarack to junior developer Talon Metals in 2014.
https://www.valuewalk.com/rio-tinto-cobalt/
Shear speculation, but is this another source of cobalt possibly being considered for refining or could it be the source considered for FT refining. From the available Rio Tinto Kennecott (expansion) reserves data available, nothing is included for cobalt.
https://www.riotinto.com/en/news/releases/2023/rio-tinto-invests-to-strengthen-copper-supply-in-us