Bog iron is a form of impure iron deposit that develops in bogs or swamps by the chemical or biochemical oxidation of iron carried in solution. In general, bog ores consist primarily of iron oxyhydroxides, commonly goethite.
Bog ore
Part of Wall with Herma—usage of bog ore in architecture
Typical iron-bearing groundwater emerging as a spring. The iron is oxidized to ferric hydroxide upon encountering the oxidizing environment of the surface. A large number of these springs and seeps on the flood plain provide the iron for bog iron deposits.
A bog or bogland is a wetland that accumulates peat as a deposit of dead plant materials – often mosses, typically sphagnum moss. It is one of the four main types of wetlands. Other names for bogs include mire, mosses, quagmire, and muskeg; alkaline mires are called fens. A bayhead is another type of bog found in the forest of the Gulf Coast states in the United States. They are often covered in heath or heather shrubs rooted in the sphagnum moss and peat. The gradual accumulation of decayed plant material in a bog functions as a carbon sink.
A bog in Lauhanvuori National Park, Isojoki, Finland
Tourbière du Lac-à-la-Tortue (fr), ombrotrophic, Quebec, Canada
Peat bog and peat to dry, L'Isle-aux-Coudres, Quebec, Canada, 1976
Precipitation accumulates in many bogs, forming bog pools, such as Koitjärve bog in Estonia.