A thin film of silver, applied by sputtering or vacuum evaporation, provides an excellent conformal conductive coating for scanning electron microscopy of insulating specimens. When no longer required it is easily removed with Farmer's reducer a dilute aqueous solution of potassium ferricyanide and sodium thiosulphate. No damage was apparent to fine structure in the calcite matrix of ostracode shells, or to other biological tissues. No problems have been encountered with grain in the silver film at magnifications up to 15,000 X, or in the storage of coated specimens in a desiccator for periods exceeding 6 months.
Mills, A. A.
"Silver as a Removable Conductive Coating for Scanning Electron Microscopy,"
Scanning Microscopy: Vol. 2
, Article 6.
Available at: https://digitalcommons.usu.edu/microscopy/vol2/iss3/6