Figure 3
Granular structures in various leaf fossil samples. (a,c,e) LM images; surface illumination, 10 × objective; (b,d,f,g,h) SEM images. (a,b) Sample ‘Ro-2.2’ (‘Sideroxylon salicites’); the LM image (a) shows leaf veins and yellow to brown globules of varying sizes embedded in a bright mineral sediment matrix; in the compositional contrast (BSE) SEM image (b), the fragmented globules appear dark, indicating organic material; minerals appear bright. (c,d) Sample ‘Ro-110.6’ (‘Magnoliopsida’); globules (not fragmented) and holes indicate weak adhesion to the surrounding sediment. Brick-like structures in leaf veins resemble crystals in fresh leaves. (e,f) Sample ‘Ro-13.3’ (‘Nymphaea nymphaeoides’); LM image shows black serrated particles and (difficult to see) smaller yellow globules. The SEM images shows empty space around granules, perhaps a result of shrinkage. (g,h) Freshly cleaved area of the leaf coal sample Ro-59.9; numerous empty cavities of various size, up to 30 µm, are distributed evenly. The detail image (h) illustrates the angular shape of the cavities which resemble casts of CaOx druses. Scale bars: (a,c,e) = 200 µm; (b,f,g) = 50 µm; (d) = 100 µm; (h) = 20 µm.
