A Leica EM ACE 600 high-vacuum coater was used for the application of a carbon coating of 30 nm in Preparation B.
The grinding and polishing of the cross-sections were done as described in Jaques and Zikmundová (unpublished). Before the sample was reached, the polishing mode was changed from wet to dry47 (link).
The first observations of the cross-sections were made under the Stemi 2000-C and Stemi 508 stereomicroscopes (Zeiss, DE) and a Reichert microscope (Reichert Technologies, US) coupled to an Axiocam ERc 5 s (Zeiss, DE).
The scanning electron microscope used for this study is a MIRA3 XMU (Tescan, CZ). Both the high-vacuum (5 mbar to 9 × 10–5 mbar) mode and the low-vacuum (0.07 mbar to 5 mbar) mode with a secondary electron detector (LVSTD mode) were used.