Authigenic precipitation of ferric oxyhydroxides and greenalite in Archean oceans

The initial mineral phases of banded iron formations (BIFs) were mostly altered during diagenesis and metamorphism. The initial iron mineral, whether it was hydrous ferric oxides (HFO) or hydrous ferrous silicates (HFS) is a matter of debate. Each of those being the primary iron mineral offers us considering completely different biogeochemical conditions of Archean oceans. Some Archean greenstone BIFs of Badampahar (~3.2 Ga), Singhbhum Craton...