goethite
In terms of relative abundance, goethite is second only to hematite (α-Fe 2 O 3) among iron oxides.Goethite is normally formed under oxidizing conditions as a weathering product of iron minerals (e.g., pyrite, magnetite).Because it is formed near the surface, goethite is the major component of the gossan of iron sulfide deposits in locations such as Arizona and of lateritic deposits in places ...