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Gunflint Chert (Paleoproterozoic, ~1.878 Ga; near Port Arthur, Ontario, Canada) 1 (45257036305).jpg - Rudolphous
Argillite (Coleman Member, Gowganda Formation, Paleoproterozoic, ~2.3 Ga; Straight Lake West roadcut, north of Temagami, Ontario, Canada) (47026090734).jpg - Ser Amantio di Nicolao
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