Examination and analysis of an Egyptian Partly gilded bronze group Statue : Case study

الملخص EN

An Egyptian partly gilded bronze group statue from the Egyptian Museum in Cairo was in a highly deteriorated condition.

It was covered with an extremely disfiguring and heterogeneous crust varying in color, thickness and nature and incorporated with soil particles in many parts.

The gilding layer sandwiched between under and above corrosion products suffers from rupture, flaking and detachment.

Characteristics of the patina and the gilding layer were revealed by Optical Microscopy (OM).

The nature of the corrosion products and the corrosive species were detected by X-ray diffractometer equipped with X-ray fluorescence spectrometer (XRDF).

The chemical composition of the metal core, the corrosion, the nature of the gilding layer and its composition were determined by Scanning electron microscopy equipped with energy dispersive spectrometry (SEM-EDS).

Copper chlorides and copper carbonate were the main corrosion compounds, while calcite and nahcolite were detected as the contamination and soil residues compounds on many parts.

The burial soil where the group statue had been buried is an aerobic calcareous soil rich of sodium chloride and natron salt.

The group statue is made of a copper tin bronze alloy and the gilding layer is of a pure or rich-gold alloy.

The gilding layer was of foils that were applied directly on the bronze surface.

The corrosion phenomenon was discussed and the conservation procedures were discussed.