Unconsolidated surface soil and dust samples of varying trace element (TE) content were collected from remote locations in central and south-eastern Australia. The finer grained fraction of the samples (<10 mm, PM 10) was separated and geochemically compared to the parent particulate matter (PM PAR). TE are mostly hosted in phosphates and oxides/hydroxides or adsorbed to clay minerals, and are normally fractionated into the PM 10 , producing PM 10 /PM PAR ratios >1, especially in siliceous, TE-depleted dusts. In contrast, samples TE-enriched by primary silicate minerals eroded from igneous and metamorphic rocks can produce PM 10 /PM PAR <1 for more mobile elements such as K, Na, Ba, Rb, and Sr. K/Rb is normally lower in PM 10 (unless the PM PAR is muscovite-rich) as is the light/heavy rare earth elements (LREE/HREE) ratio because both Rb and HREE are preferentially adsorbed by fine clay particles. Zr and Hf are mostly hosted by zircon crystals initially >10 mm but these diminish in size with time and sedimentological transport so that PM 10 aerosol concentrations of these elements are typically telescoped into a narrower range than the PM PAR . Nb is strongly fractionated into PM 10 , with Nb/TiO 2 ratios characteristic of the durable host mineral rutile in all but the most TE-enriched PM. TE content of PM 10 in continental dusts is controlled by both physical and chemical processes. Fresh primary silicates suppress PM 10 /PM PAR ratios of TE with low ionic potential, whereas the opposite effect is induced by hydraulic sorting and/or physical attrition during surface transport, as well as clay absorbtion and fixation of TE in small, resistant accessory minerals. Additional keywords: trace elements, PM 10 geochemical fractionation, continental dust.