Autometallography. A new technique for light and electron microscopic visualization of metals in biological tissues (gold, silver, metal sulphides and metal selenides).

The autometallographic procedure represents a new technique that can substitute for the normal methods of physical development (PD). The physical developer (a solution of reducing substance, silver salt and protection colloid) is replaced by a photographic emulsion and chemical developer. Accumulations of gold, silver, metal sulphides and metal selenides can be amplified by the present technique. Tissue sections placed on glass slides are covered by a silver bromide containing emulsion, dried and exposed to a chemical developer. After development the emulsion is either removed or cleared and the sections are counterstained and embedded. The autometallographic procedure can also be applied to ultrathin sections.