25 March 2005
Reason for treatment
Examination & treatment.
The object is set in a Plaster of Paris mould and is very fragile. It is very dusty. The intonacco is delaminating from the mud plaster in several areas but particularly around the edge. There is evidence of salt efflorescence. The paint layers have suffered losses. There are several areas of loose and detached paint flakes. There ae numerous cracks in the intonacco as well as several cracks extending into the mudplaster. The plaster of Paris surround has caused dark staining approximately 3" wide around the edge. The mudplaster appears to be very soft and crumbly.
The object was thoroughly examined under a microscope. Observations on ancient painterly techniques, past treatments and present treatments were recorded individually as technical information record on hard copy (see envelope for detailed information). A photoshop file detailing the objects condition, observations on painterly technique, past and most current treatment is also available on memory stick.
The object was lightly dry cleaned with low suction vaccuum cleaner.
The paintlayers were consolidated with 15% Vinamul 3252 (vinyl acetate,ethylene copolymer) in deionozed water using IMS as a wetting agent. Powdery areas were consolidated with 2% Paraloid B72 (ethyl methacrylate copolymer) in Acetone (propan-1-one/dimethyl ketone)/IMS. The top layers of the Plaster of Paris was removed from the sides with a minidrill and the arricio(mudplaster) was consolidated with 20%Vinamul 3252 (vinyl acetate,ethylene copolymer) using IMS as wetting agent. A paste of microcell glass balloons in 20% w/v Paraloid B72 (ethyl methacrylate copolymer) in Acetone (propan-1-one/dimethyl ketone)/Industrial methylated spirits (ethanol,methanol)(1:1) was applied to the exposed arricio collar to act as an interfacee between it and the new collar enabling future reversibility. A ready made paste of Pollyfilla Plaster Repair was used to replace the removed plaster of Paris layers of the collar. The new mount collar was set back from the edge of the arricio by approximately 5mm.