Understanding the mechanisms by which fine solids are recovered to bitumen froth during oil sands extraction plays a critical role in minimizing the detrimental effect of fines on bitumen recovery and froth quality. A simple method was presented in this study to distinguish fine solids recovery by water entrainment from that by true flotation. Dispersed air flotation was carried out, using a 1-L Denver flotation cell, to evaluate flotation behaviours of different sizes and types of fine solids (<5 mu m up to <40 mu m silica, <5 mu m kaolinite clays, and < 44 mu m fine solids extracted from oil sands). The results show that dispersed individual fine solids in oil sands slurries could be recovered to the froth by mechanical entrainment, and by true flotation. While the recovery of hydrophilic fine solids decreased with increasing particle sizes by water entrainment, the recovery of hydrophobized fine solids, due to dodecylamine adsorption, increased with increasing particle sizes by true flotation. Fine solids extracted fromoil sands behaved differently from pure silica or clays: they adsorbed amine slowly, and responded to flotation slowly. The exact reasons remain to be explored.