Tate Sculpture Conservation
The Conservation of John Foley's Sir Joshua Reynolds P.R.A. In 2005 Tate Britain mounted a display about the artist Sir Joshua Reynolds (1723-1792).
At the entrance to this exhibition curators chose to display a large, marble statue of Reynolds by the sculptor John Henry Foley. The sculpture had not been displayed for several decades and was known to be extremely dirty. Made of one block of carved white marble, the sculpture is a larger-than-life, full-length portrait of Reynolds as President of the Royal Academy. It was covered in a sooty, greasy black-brown dirt, with yellowed areas due to frequent handling.
There were also spatters of red paint on the cloak the artist is shown wearing. Examination under ultra violet light showed that no previous coatings were present. The sculpture was vacuumed to remove loose dust and dirt. Tests were then done using several different cleaning methods which included steam cleaning, laser cleaning, detergent solutions, solvents and poultices. Each method's effectiveness at cleaning the sculpture without damaging the marble was assessed by detailed examination under a microscope.
The cleaning method eventually chosen was a poultice containing a buffer and agents to increase its adherence to the near vertical surfaces. This was left on the sculpture for three and a half hours; once the poultice was removed the surface was cleaned with a buffered solution. Very dirty areas had a buffered gel applied to remove the yellow discolouration. The red paint marks were removed using solvents.
The sculpture was in very good condition after cleaning; however, the cleaning process had revealed a discoloured wax fill on the face in what appeared to be a drill hole. This hole could have been made during the measuring up of the sculpture, or it may have been purposely drilled in order to remove a disfiguring stain in the marble. Tate's conservators decided to disguise the discolouration by removing the top layer of wax and applying a removable plug of material coloured to match the appearance of the marble.