Fig. 3

SEM images and EDS spectra of Saharan dust particles collected in Cabo Verde, 29 Feb 2008 (Jeong and Achterberg 2014). Images were acquired at an acceleration volatge of 5 kV and a working distance of 7 mm using a TESCAN MIRA 3XMH field emission SEM. EDS spectra were acquired originally in the range of 0–15 keV using an Oxford X-MAXN 50 detector. Bottom image of each panel was magnified from top image. Coarse mineral grains are coated with the coatings of submicron clay minerals. Coarse minerals are quartz in (a), plagioclase in (b), Na-rich plagioclase (albite) in (c), K-feldspar in (d), illite/muscovite in (e), chlorite in (f), calcite in (g), dolomite in (h), gypsum in (k), and palygorskite in (l). i Aggregate of kaolinite. j Aggregate of ISCMs. Arrows in (d) and (h) indicate gypsum (Gp) blades. Arrows in (a) and (i) indicate hexagonal kaolinite (Kln) plates