The scanning electron microscope (SEM), coupled with an analytical device (EDS), was used to examine very small samples of alteration salts on an enamel-copper object. Some complementary mineralogical analyses were carried out by x-ray diffraction (XRD). Morphological examination by SEM showed a limited deterioration of the enamel glass; conchoidal fractures and numerous bubbles were observed. The EDS analysis found external and internal zones enriched with alkaline elements (potassium, sodium) and free silica (quartz). Partial devitrification had developed in these zones. The composition of the glass was determined (silicone, aluminum, calcium and sodium); two different kinds of glass can be distinguished by lead content. The colorants of enamels are metallic oxides: cobalt for blue, iron and manganese for yellow, red and brown. The study revealed the precise nature of alteration at the interface of enamel and copper salts (sulfates and chlorides are always present). Gypsum was present everywhere on external surfaces. The restored zones were isolated by SEM observation of coccolithes emanating from blanc de Meudon (calcium carbonate), a preparation commonly used in the 19th century for restoration.