Formula : FeOOH

Space group: 
Orthorhombic - Dipyramidal HM symbol (2/m 2/m 2/m) Space Group: Amam
Dana class: - 6 Hydroxides and Oxides Containing Hydroxyl ; 6.1 Hydroxides and Oxides Containing Hydroxyl where X+++O OH ; 6.1.2
High temperature: 
In the presence of pure water lepidocrocite is stable at all temperatures between OC to 100C. Lepidocrocite gives a d.t.a. curve similar to goethite with an endothermic peak at a temperature of 350C to 390C and an small exothermal peak at 370C to 500C .
Geological context: 
Lepidocrocite is a very common mineral typically occurring as a weathering product of iron-bearing minerals such as siderite, magnetite, pyrite, etc. It is normally formed under oxidizing conditions.

Dernière mise à jour le 25.01.2021


T(°C) 0 25 60 100 150 200 250 300
log10K 2.99 1.85 0.54 -0.64 -1.82 -2.81 -3.69 -4.55