Melezhik, Filippov and Romashkin (2004) describe the geology of the giant Palaeoproterozoic shungite deposit in Karelia: how big it is, how it formed, where it sits in the geological column. Foundational paper for anyone trying to understand the source rock itself rather than the wellness claims.
Sources: via
littlelemuria.com
· original: Ore Geology Reviews
DOI 10.1016/j.oregeorev.2003.08.003
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