Large blocks (to 25 tons) of native iron were found by Nordenskiöld in 1870, and brought to Sweden as meteorites. It was later found out that iron occurred as nodules in basalt, formed by reduction due to incorporation of carbon-rich sediments.
Ref.: Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II: 40.
Geochim. Cosmochim. Acta 54, 57–70.
