The placing of metal oxide pillars between clay layers is used to modify clay properties such as surface area, acidity, and catalytic activity. The resulting material can be used as a catalyst for degrading environmental contaminants or as an adsorbent for pesticides and other organic molecules. Pillars with varying Fe:Al ratios were intercalated into synthetic laponite or montmorillonite by combining an Al and/or Fe oligomer (Al +Fe=100%) with a 2% suspension of the clay, then heating the mixture at 300ºC for 12 h. The Fe oligomer was prepared by hydrolyzing FeCl₃ in aqueous solution, then adjusting the pH to 2.2 with Na₂CO₃ . The Al oligomer was obtained by hydrolysis of AlCl₃.6H₂O with NaOH at pH 4.4. The pillared clays and the Fe oligomer alone were characterized by variable temperature Mössbauer spectroscopy and chemical analysis. Results revealed that the Fe oligomer was a pure Fe oxide phase, most probably akaganeite, with a range of particle crystallinities. Heating the Fe oligomer alone to 300°C transformed it to hematite, but no transformation occurred if heated after intercalation between the clay layers. Introduction of Al into the pillar had no effect on the magnetic hyperfine field of the Fe pillar, indicating that Al forms separate pillars rather than substituting for Fe in the akaganeite pillar. The pillar-forming process evidently did transform some of the Fe in the pillar into a non-magnetic phase that resisted reductive dissolution by citrate-bicarbonate-dithionite (CBD).