Conservation treatment of Lavinia Fontana's painting

View through a window into a conservation studio where two women work on a large oil painting — Conservators Maria Canavan and Letizia Marcattili work on the painting in the conservation studio. Photo © National Gallery of Ireland.

From stabilisation to retouching to repairing the frame.

Every conservation treatment aims to restore stability to the artwork and to ensure its aesthetic value can be fully appreciated.

Read on to discover the treatment carried out on Lavinia Fontana's painting The Visit of the Queen of Sheba to King Solomon (1599), by conservators Maria Canavan and Letizia Marcattili, as part of the Lavinia Fontana Conservation and Research Project.

First steps: secure and stabilise

Close-up view of two hands holding tools against a damaged area of an oil painting

The first steps were to secure and stabilise areas of loose and fragile paint and canvas, and to address the underlying causes of instability.

The consolidation was carried out using an adhesive specially formulated for conservation. Areas of deformation were also treated with the aid of a mobile suction plate to bring them back to plane. Historic damages to the canvas were mended with inserts to reconstitute an even and sound fabric support for the painting (above right).

Varnish and overpaint removal

Close-up view of a blue-gloved hand wiping an oil painting of two women's faces.ing cotton swabs

Varnish and old overpaints removed using small cotton swabs.

Areas of discoloured varnish removed from the upper parts of a painted face

The dramatic difference between cleaned and uncleaned areas of the painting.

The upper layers of varnishes and the retouchings, originally applied in the 1960s, had yellowed due to natural ageing. This yellowing altered our perception of the original colours of the composition.

Over several months, the varnish and the old overpaints were selectively and carefully removed using small cotton swabs (above left) with a solvent mixture formulated according to analytical tests on the painting.

The removal of these discoloured materials revealed the hidden brightness and vibrancy in the original paint. A dramatic difference is now apparent in the saturation and legibility of the darker colours in the painting (above right).

Surface adjustments

A conservator working on an oil painting

Letizia Marcattili brings the surface of the repairs into plane with the original surface.

Two conservators applying isolating layer of varnish to a large oil painting

Conservators Letizia Marcattili and Maria Canavan apply an isolating layer of varnish to the surface of the painting.

A gesso filling material was applied to bring the areas of historic paint loss into plane with the surface of the painting, and to provide a stable base for the new retouchings. Once the aged coatings were removed, an isolating layer of varnish was applied across the surface. All of the varnishes and retouching media that we use during the treatment are applied over this removable layer. Conservators follow the principle of minimal intervention for practical treatments, using materials that are reversible and have known ageing, stability, and solubility properties. This should help to reduce the frequency and risks of future treatments.

New programme of retouching

Close-up of King Solomon's head in Fontana's painting showing areas of loss before retouching

King Solomon's head before retouching.

King Solomon's face after paint losses have been retouched

King Solomon's head after retouching.

In order to re-integrate areas of loss and damage in the paint layer and allow the painting to be viewed as a whole, a meticulous retouching campaign was carried out over the course of several months. This is a painstaking process involving the application of retouching colours using tiny dots and lines. These retouchings remain distinguishable at a very close range and so they cannot be mistaken as original paint.

Treatment of the frame

Damaged corner of an ornate gilded frame for a painting

Dirt being removed from a gilded picture frame with a cotton swab

Dirt is removed from the gilded surface using a cotton swab.

Little is generally said about picture frames. However, a painting's frame can not only function as a decorative surrounding, but also as protection for the more exposed and fragile edges, and as a stable structure to carry its weight.

Damaged corner of a gilded picture frame being repaired

A damaged corner of the frame.

Broken corner of gilded picture frame being repaired with a wooden insert

The wood was consolidated and repaired with new wooden inserts.

The gilt wooden frame that adorns Lavinia Fontana's canvas was probably added after the painting’s acquisition by the Gallery in 1872. The frame had numerous issues that needed to be addressed. The structure was unstable at the corner joints, with many areas of loss. Furthermore, the golden surface appeared dull and was covered with darkened gold paint and discoloured varnishes.

The conservation treatment of the frame involved adding an auxiliary support at the back to strengthen the joints which tended to twist. Aged and discoloured coatings were removed from the surface, revealing a gold leaf still bright and in a quite good condition. With filling and retouching of lost and damaged areas complete, the frame could finally resume its aesthetic and protective function for the painting.