bog iron
Noun
Meaning
English Wikipedia has an article on:bog ironWikipedia
bog iron (uncountable)
(geology) deposits of mixed oxides and hydroxides of iron formed when iron-bearing groundwater emerges onto the surface
Synonyms
Examples
However most iron as well as its forging was of domestic origin, probably from bog iron.
Iron ore was available throughout the country, including bog iron extracted from the ore in peat bogs in the north, the natural iron-bearing balls found in the Veluwe and the red iron ore near the rivers in Brabant.