The stability of oil sands tailings sludge with respect to sedimentation and consolidation is often attributed to the colloidal properties of some of the component minerals like clays. In this study, the packing structure of particles in a real oil sands sludge is compared with that of montmorillonite colloidal sediments published previously. For this purpose, the technique of hypercritical drying was used and the dried samples were examined under a scanning electron microscope. The network structures of both materials show many similarities. In particular, the platelike clay particles build a random network by linking to each other according to an edge-to-edge fashion.