Removing Gold Coating From Sem Samples

An essential tool in micropalaeontological studies is analysis and imaging using a scanning electron microscope (SEM). It is commonly necessary to coat the sample with a thin layer of gold or gold‐palladium alloy in order to prevent charging of the surface, to promote the emission of secondary electrons so that the specimen conducts evenly, and to provide a homogeneous surface for analysis and imaging. However, coating a specimen with gold is a semi‐destructive process that masks the surface of specimens, and a common curatorial practice is to prohibit coating of important specimens. We describe a non‐destructive, simple and inexpensive technique that uses KCN (or NaCN), a glass jar, paper towels, cardboard and a fume hood for the removal of gold coatings from SEM samples. This technique requires little additional handling of the specimen, and there is no need to place the specimen in a solution.