A simple method for microtome sectioning of prehistoric charcoal specimens, embedded in 2-hydroxyethyl methacrylate (HEMA)

Abstract

A simple method for microtome sectioning of prehistoric charcoal, embedded in 2-hydroxyethyl methacrylate, HEMA (= glycol methacrylate, GMA), is described in detail. Procedures for dehydrating, embedding, polymerization and sectioning are, with the exception of some modifications due to the specific texture of charcoal and the relatively large size of the specimens, identical with those used for recent botanical specimens. The sections can be observed directly under the light microscope without further treatment (e.g. staining). Low costs and the rapidity of preparing slides (completion within 24–36 hours), combined with the superior quality of the sections, makes this method best suitable for species analysis of charcoal specimens with problematic anatomy requiring detailed examination of characteristics.