Treatment of the frame for Benjamin West’s Devout Men Taking the Body of Saint Stephen:
Most of the current action involves careful cleaning and discussion about the best approaches to return the frame to its former glory. Over many years air pollutants settled on the frame, forming a layer which obscures the brightness of the gilded surfaces. Imagine the oily coal soot polluting London during the Industrial Revolution. As seen below, cleaning the accrued dust and grime from the past century exposes the frame’s surface.
Undisturbed for decades, dust sticks to the gilded surface in thick sheets. Conservators wear dust masks and use Japanese soft-bristle brushes, called hake, to loosen the dust before it can be sucked away it into a HEPA filtering vacuum. Clouds of dust are visibly lifted away during this process.
After dusting, conservators clean soot and dirt from the surface using a variety of techniques. The ornamental decorations of the frame become more defined after cleaning.
Underneath all the dust is a surface gilded with gold leaf. Unfortunately, there is also a thin layer of bronze paint atop the gold. Bronze paint appears bright like gold when first applied, but tarnishes to a flat brown color, usually within only decades.
This bronze paint layer is estimated to be about 100 years old. It was probably brushed on to brighten the gold surface which had become damaged, dirty or dull. Conservators are researching a blend of solvent solutions to remove the bronze overpaint without damaging the gilding layer below. Below, solvent testing research is done on small areas. Vents with charcoal filters remove the solvent fumes, and microscopes are used to investigate the cleaning results.
The frame’s flaking surface, seen below, is another problem that will need to be addressed. Gessoed and gilded wood surfaces often show signs of flaking caused by relative humidity and temperature fluctuations over time. In this case, there are several layers of surfaces to consider when consolidating. Conservators will next focus on the complex multiple layers of gilding and overpaint in more detail.