Silicon isotope compositions and elemental (Ge, Al, Fe and Si) concentrations were measured on clay-sized fraction (b2 μm) extracted from all the horizons of the four soil profiles in Cox Bay (clay-CB 120 years; clay-CB 175 years; clay-CB 270 years; clay-CB 335 years) and the undated podzolic soil profile in Gaume (clay-G), and also on parent material of soils in Cox Bay (sand fraction of the beach sand; Beach-CB 0 year).