The main framework of the screen, the arch and the quadrant details are constructed from wrought iron bar. The screen is supported by six slender columns in iron and brass. The iron is decorated with punched and stamped geometric designs and painted in polychrome with leaf gilded embellishment. The basic iron structure is further decorated with scroll, leaf, stud and flower elements in polished brass. The columns are formed by clusters of polished brass tube and hexagonal cast iron sections decorated with polychromed and leaf gilded stencilling. The capitals are surmounted by bronze figures of angels with St Michael in the central arch below the cross.
The condition of the wrought iron was generally very good with little active corrosion and no evident structural problems. The condition of the paint was also reasonably sound but had suffered from fading and matting of colour and a significant build-up of surface dirt, which gave the screen a dull appearance. The paint used was almost certainly lead based, which when first applied would have been semi-gloss and after time this naturally matts-off and the colours soften.
The brass work was by that time all very dull and tarnished, there was plenty of evidence that this was all originally lacquered with a gold tinted natural shellac over a bright polished brass surface.
The structural condition was sound, so it was decided the best way to approach the conservation would be to leave the main iron framework of the screen in place and remove only the decorative brass and gilded elements to the studio, for cleaning and lacquering.
The brass work was held onto the surface by many small screws and bolts, all of which were numbered and tagged along with the decorative elements as they were removed from the screen. They were all wrapped and boxed, then transported to the studio to be cleaned and lacquered.
All of the brass decorative detail had been previously lacquered, most of which had broken down allowing the brass to tarnish severely. Before polishing and cleaning could begin, this had to be removed. This was done chemically by lifting any deposits of old lacquer from the surface. The details were then washed in water to remove any chemical deposits, then dried thoroughly. The surface was then polished by hand with a polishing cream using soft cloths and brushes. They were then degreased and lacquered with a shellac based lacquer.
The bronze figures of St. Michael and the Angels were originally gilded, evidence of this was found beneath the decaying gold paint that had been painted over the worn gold, at some time in their past to restore the surface. This gold paint was removed, the surface was then primed ready to be gilded with two layers of 16g, 23.5k English gold leaf. When this was done, the upper surfaces were burnished.
The main framework of the screen was cleaned and surface treated in some small areas for rust corrosion, and then a thin diluted coat of a matt, casein based paint was applied over the surface, carefully colour matched to the original colours and texture of the painted surface. The intention of this was to lift the colour and surface of the paint without losing the original paint itself.
The brass elements were systematically reinstated in their original positions with their original screws. Great care had to be taken not to damage any of the lacquer in this process. We also lacquered the heads of all the cleaned brass screws after they had been tightened in position, so that the visual impact of the polished brass would not be marred by dull tarnishing screw heads.