Figure 5
Blank Runs and other dusts. Lamp illumination occurred near the start time shown for all runs. (A) A blank (no dust) prepared by pipetting water into LN2 in the sample chamber or (B) pipetting water into LN2 outside the chamber and crushing with a mortar and pestle. Neither blank shows a significant fractionation; however, they give an idea of the degree of non-uniformity of disaggregated samples. Mixtures prepared analogously to panel B, but with different dusts are shown in the bottom three panels. These dusts are (C) 1 wt% SiO2 in 1-2 μm particles (D) 25 wt% TiO2 in 1-2 μm particles and (E) 5 wt% cuttings from the Fukang Pallasite in 1-50 μm particles. All three dusts show some increase in fractionation over time.