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Fig. 3. (a) Scanning electron microscope (SEM) image with corresponding energy dispersive X-ray (EDX) spectra of representative clay sized particles in SP1B1 clay size fraction. Region "Fe" illustrates a typical iron-oxide coating with substitution of Ti and Mn. Region "k" corresponds to underlying kaolinite matrix. (b) SEM image of a large aggregate encountered in SP2B1 water-dispersible silt fraction. (c) SEM image of a Ni phase with Cu- and Ni-rich region indicated. Both metals are anthropogenic in origin. Phases such as this one may represent source term artifacts, surviving decades of weathering, or the resulting secondary weathering products.
