Device: PANalytical EMPYREAN; CuK[Alpha] radiation (40 kV, 40 mA)Method: Each sample was analyzed between 2.5° and 29° 2 Theta, with a step size of 0.013° in the air-dried state and after ethylene glycol solvation. X-ray diffraction measurements were performed on organic and carbonate-free, preferentially oriented clay-size filer cakes (< 2 µm) with molybdenite as an internal standard. Further details of sample preparation techniques are described in Petschick et al. [1996] and Diekmann and Kuhn [1999]. Diffractograms were evaluated using the "MacDiff 4.2.5" software [Petschick et al., 1996] without using a weighted average smoothing but applying a molybdenite (006) peak correction.