Ferricrete
From Wikipedia, the free encyclopedia
Ferricrete is a mineral conglomerate consisting of surficial sand and gravel cemented into a hard mass by iron oxide derived from the oxidation of percolating solutions of iron salts. The word is derived from the combination of ferruginous and concrete.
Ferricrete is used widely in South Africa to create roads in rural areas. It is better known in these regions by its Afrikaans name "Koffieklip" (coffee stone)
Ferricrete is also found in the United States in areas of the Gulf Coastal Plain and the Atlantic Coastal Plain.