Wikimedi'Òc

Boulder Point, Presque Isle Bay, by Childs, B. F..jpg - Dcoetzee

Ontonagon Copper Boulder.jpg - Ian Shackleford

Glacial copper boulder (Mesoproterozoic, 1.05-1.06 Ga; near Houghton, Keweenaw Peninsula, Michigan, USA) (17269890716).jpg - Natuur12

Geological report on Monroe County, Michigan (1900) (14785835623).jpg - SteinsplitterBot