The Frame Blog

Proposing a critical decision-making framework for gilded wood conservation

by Malgorzata Sawicki

Introduction

The conservation of gilded wood – from architectural interiors, polychrome sculpture, altarpieces, panel paintings, furniture, to picture frames – presents a nexus of complex material, aesthetic, and ethical challenges. A conservator specialized in this field, determining whether, where, and how to intervene in the life of such an artefact, needs to keep a careful balance between maintaining historical and material integrity and reinstating sufficient aesthetic unity for the object to be understood.

Part of the Alcove, Sala dell’Alcova, 17^th century, Palazzo Reale, Turin

Historically, gilding in conservation was treated similarly to varnishing a picture: when worn or dirty, the finish was often replaced to restore a sense of newness and to appeal to the purchaser [1]. Through the centuries gold signified prestige and eternity, so traditional restorers tended to preserve the craft process of gilding rather than the  material integrity of the object, leading to the creation of new gilded surfaces which concealed or destroyed original material [2]. As heritage conservation developed into a scientific and academic discipline, and shifted toward minimal intervention, ethical assessment, and respect for the physical and historical authenticity of an object, the approach to the conservation of gilded objects changed as well. Today, conservators generally recognize that overall regilding can compromise historical integrity, creating an unacceptable intrusion into the material biography of the object [3] . Yet, without specific ethical guidance for gilded wood conservation, decisions about materials, treatment extent, or non-intervention still depend heavily on individual judgment. This paper addresses that gap by proposing a structured decision-making framework to make such judgments more transparent, analytic, and ethically grounded.

Detail of the Sala di Saturna, Palazzo Pitti, Florence

Ethical foundations for intervention in gilded wood conservation

The ethical landscape of contemporary conservation practice has been profoundly shaped by Cesare Brandi’s Teoria del Restauro [4]. His principles, universally applicable in heritage conservation, are especially challenging in gilded wood conservation, where the boundary between preservation and restoration is often exceptionally fine [5]. For complex, composite giltwood objects, the core theories of minimal intervention, reversibility, and authenticity are not abstract ideals but principles with direct and often irreversible material consequences [6].  The gilded wood conservator is therefore frequently placed in an ‘invidious position’, compelled to reconcile competing demands [7] . On the one hand, the historical and scholarly imperative requires the preservation of authenticity and the object’s ‘marks of age’ [8]. On the other hand, the aesthetic requirement demands that the viewer be able to appreciate the gilded finish without severe visual disruption caused by damage or loss [9] .

Conservation is understood as a ‘critical act’ which must carefully balance the historical evidence of an artwork with its aesthetic demands [10]. Professional conservation guidelines require that all interventions be governed by respect for the physical, historical, and aesthetic integrity of the object. However, contemporary conservation theory, particularly the work of Salvador Muñoz Viñas [11], has challenged conservators to recognise that conservation itself is a cultural construct: any intervention inevitably alters the object, and every decision is shaped by subjective judgment, personal conviction, and expectation.

The principle of minimum intervention holds that the primary aim of conservation is to stabilize and protect an object while introducing as few alterations as possible to its original fabric and historical integrity [12]. In the context of gilded wood conservation, this may prioritize the consolidation of delaminating gesso layers and the stabilisation of a failing wooden substrate of frame over their complete replacement.

Details of picture frames showing brass-based overpaint. Author’s photo

At the surface level, it requires cleaning methods capable of removing disfiguring overpaint without abrading or otherwise compromising the original gilding. This principle therefore constitutes a central ethical constraint on highly restorative treatments, such as overall regilding, which, by definition, involve either the application of a new finish over earlier layers or the substantial removal and replacement of historic material with new gilding. It directs the conservator instead toward the minimum intervention treatment necessary for the long-term preservation of the gilded object.

The ideal of reversibility requires that any treatment should be removable in the future without damaging the original object [13]. This presents a significant challenge in the conservation of gilded surfaces. The use of traditional gilding materials in treatment can make reversibility highly uncertain. As the new restoration materials are often chemically identical to the original layers, they respond to the same solvents. Consequently, if a future conservator needs to remove the restoration, traditional gesso fills and blended bole layers make it nearly impossible to define the boundary between the original and the restored surface. Reversing the treatment therefore carries a high risk of inadvertently removing or damaging the original historic substrate.

Because absolute reversibility is often restrictive and practically difficult to achieve, heritage conservation has increasingly adopted the concept of  ‘retreatability‘, meaning that an object can be treated again in the future without compromising further intervention [14]. This aligns with Brandi’s theory that current interventions should not hinder, but rather facilitate future conservation efforts [15]. In the context of gilded objects, retreatability presents specific challenges and has prompted changes in modern conservation practice, including the adoption of contemporary synthetic materials, selected for their known ageing properties and reliable solubility [16]. However, the evaluation of how reversible they will remain in the future is difficult, particularly if the treatment itself – such as, for example, consolidation of powdering foundation layers – is practically impossible to reverse.

Authenticity and integrity remain among the most philosophically complex concepts in conservation. Authenticity is closely linked to truthfulness and the genuine [17]. Yet defining authenticity simply as ‘originality’ is limiting, because it confines the idea to the moment an object is created, and fails to acknowledge that, despite physical changes caused by natural ageing or human intervention, an object may continue to convey its original underlying concept centuries later [18]. Conservators should therefore neither aim to return an object to its presumed original state nor undertake treatments intended to recreate its condition at the moment of creation [19].

Brandi argued that restoration should aim to re-establish the ‘potential unity’ or ‘oneness’ of the artwork, whilst simultaneously respecting its historical dimension and avoiding the creation of either an artistic or historical forgery [20]. This theoretical framework, further developed by Paul Philippot [21], requires a delicate balance between preserving historical authenticity and recovering aesthetic unity [22]. Conservators must therefore reduce the visual disruption caused by material losses without introducing conjecture, which would compromise the genuine historical narrative of the object [23].

Decision-making dilemmas in the conservation of gilded surfaces

Details of picture frames showing brass-based overpaint. Author’s photo

Historically, giltwood surfaces in poor condition were frequently regilded or repainted with brass-based coatings which concealed damage and earlier repairs, but often also obscured the original design. Brass particles mixed with binders such as oil, wax, shellac, natural or synthetic resins were applied over worn gilding to imitate bright gold [24]. Over time, these coatings discoloured, forming dark patches or continuous dull layers. In some cases, the brass overpaint or brass leaf (schlagmetal) used to imitate gold reacted with oil or synthetic binders to form copper carboxylates, visible as green corrosion products which permanently altered the original gilded surface [25].

Details of frames showing green metal-soap deposits on surfaces painted with brass-based paints or gilded with brass leaf (imitation gold leaf or schlagmetal). Green copper carboxylates may be visible in close-up images of the gilded surface or may form beneath brass-based overpaint and become exposed during overpaint removal. Author’s photo

Therefore, a gilded object, such as a gilded frame, possesses often at least three authentic states: 1) its original appearance as intended by the maker – brilliant, reflective, and immaculate (if sometimes originally toned); 2) its aged state, which bears the patina of age and the evidence of use and wear; and 3) a state showing the scars of its history with previous interventions.

The central ethical question is: which state should guide the conservation treatment? – the lustrous, recreated gilded surface; the worn, abraded surface which records centuries of handling, cleaning, light, and air; or the dark, dull brass-based overpaint which differs from the originally intended gilding and may no longer enhance the painting it frames. This trichotomy shapes the debate between regilding (new gilding over existing or removed layers), in-gilding (limited strictly to areas with losses, often requiring overpaint removal), and in-painting (non-gold-leaf compensation confined strictly to losses). Ethical intervention therefore requires clear articulation of the aesthetic, historical, and functional values of the object. Regilding may restore aesthetic integrity but sacrifice historical evidence, while stabilizing the aged, overpainted state favours historical integrity at the cost of aesthetic ‘oneness’ and original intent.

Common conditions of picture frames prior to conservation treatment, Author’s photo

A 17^th century frame prior to treatment may contain a careful 19^th century regilding and 20^th century brass-based overpaint. Are these layers authentic evidence worthy of preservation, or disfiguring accretions which obscure the original intent? Minimal intervention may support retaining stable later campaigns rather than invasively removing them to expose fragmentary 17^th century gilding. Yet the ethical question remains: whether the overpainted frame still contributes to the aesthetic and historical values of the 17^th century painting it surrounds?

Common conditions of picture frames prior to conservation treatment. Author’s photo

This highlights the conservator’s deeper rôle: not merely preserving an original moment but managing a stratigraphy of time. Favouring one period by removing later repairs is a curatorial act with ethical weight and irreversible consequences, making the giltwood conservator an arbiter of history and authenticity [26].

Frame conservators are often asked to answer curatorial questions, because expertise in frame history and ornament is not a widespread skill. Their advice shapes treatment planning and institutional justification, requiring skill at the intersection of science, craft, material history, and ethics [27]. Attribution, dating, provenance, and the frame/painting relationship may depend upon technical evidence hidden in style, tool marks, materials, surface stratigraphy, water- or oil-gilding, later alterations, and ornament replacement.

Although frames have often been overlooked as silent partners to paintings [28], their function is to support and enhance the artwork visually, so treatment decisions are frequently guided by the presentation of the painting as well as the condition of the frame. This symbiotic relationship requires practitioners constantly to balance the historical integrity of the frame with the presentation of the painting, making the rôle of the frame conservator uniquely complex. In many cases, the frame conservator therefore becomes a crucial liaison between object-based evidence and curatorial interpretation. Consequently, frame conservation requires balancing historical integrity with display needs and translating material evidence into arguments about significance. Conservation decisions emerge through interdisciplinary negotiation, where specialist frame knowledge can reshape the perceived values of an object and the ethical limits of intervention.

Treatment options in gilded wood conservation: ethical and practical considerations

In response to ethical questions around authenticity and minimal intervention, heritage conservation has increasingly adopted formal decision-making models [29].  These frameworks make treatment decisions transparent, explicit, and defensible by helping conservators weigh, systematically, competing values, the interests of all those involved, and the available evidence [30].

Together, these models recast conservation, not as diagnosis followed by treatment, but as a structured negotiation of multiple – often competing – values through risk analysis. The decision-making model becomes a tool for communication, collaboration, and mediation amongst those involved [31].

Values-based and risk-assessment approaches now shape conservation decision-making across disciplines, and gilded wood conservation, though a later participant in this discourse, faces comparable challenges.

Effective use of any framework first requires specialized understanding of the object. For gilded wood, this means reading its history, stratigraphy, degradation, original techniques, later restorations, alterations, and surface condition; these factors drive decisions about regilding, in-gilding, or in-painting.

Alongside condition assessment, technical examination and the scientific analysis of gilded surfaces address key questions which guide treatment [32] :

1. Stratigraphy: what layers lie above the wood, and how many gilding, regilding, repainting,     or finishing schemes are present?
2. Techniques: which original and later gilding or overpainting techniques were used?
3. Materials: what materials, especially binders, occur in each layer?
4. Date: when was each finishing scheme approximately applied?
5. Significance: how does each finishing scheme contribute to the context and values of the object?

Ethical deliberation and scientific assessment culminate in choosing an intervention. For damaged giltwood, this usually means deciding amongst overall regilding, localized in-gilding, and compensatory in-painting, but the choice depends on more than current condition. Conservators must often remove soiling and poor past restorations while protecting fragile original gilding. Historically, worn frames and sculptures were often subjected to ‘wholesale restoration’ with bronze powders, cheap oil gilding, or thick, intractable glues [33]. Removing such modern overpaints without damaging water-sensitive gesso and gold leaf requires careful scientific assessment and close attention to stratigraphy [34]. In complex cases, a recent disfiguring brass-based overpaint may be removed while an earlier, historically significant or aesthetically acceptable restoration is retained.

Left: double-sided icon of Christ Pantocrator, 12^th-13^th & 14^th centuries, after conservation; right: the 17^th century paint layer and decorative metal reliefs transferred from the surface of the mediaeval icon to a separate modern panel; Nessebar; National Gallery, Sofia, Bulgaria. Photos: © Dana Decheva

Whereas earlier ‘purist’ approaches sought to expose an original layer, contemporary conservation often treats older restorations as part of the material biography of an object – as for example, in the conservation of the Nessebar 12^th-14^th century icons, where 16^th and 17^th century overpaintings were preserved for their cultural and evidential values [35]. Treatment possibilities therefore exist on a wide spectrum between non-intervention and stripping back to the original remnants. These options are not merely technical choices but philosophical positions, requiring negotiation between aesthetic recovery and the ethical imperative to preserve historical integrity.

A basic comparative analysis of the main interventive strategies for gilded surfaces – regilding, in-gilding and in-painting – is presented in Table 1.

Table 1 Comparative analysis of interventive strategies for gilded wooden surfaces (click for larger version)

Overall regilding

Overall regilding is the most invasive intervention, aiming to return an object to an assumed ‘original’ aesthetic or functional state. It puts visual unity and splendour before material evidence, and is now generally considered undesirable because it imitates the original finish whilst erasing historical information. As Philippot argued [36], the ‘original state’ is an abstract idea rather than an historical reality, since removing later interventions and re-treating the surface inevitably modifies the original material.

Netherlandish school, High altarpiece with the Last Supper, Crucifixion and Christ Triumphant, c.1699, carved and polychrome giltwood, restored in 1997, Oslo Cathedral

Regilding is usually considered where aesthetic or functional requirements dominate, such as restored architectural interiors or exteriors, furniture in continued use, or devotional objects belonging to communities requiring symbolic splendour. Even then, the new surface is often toned or aged to avoid an overpowering appearance. Such decisions can create tensions between the expectations of those involved and the ethics of conservation, as happened in the case of the Baroque altarpiece  in Oslo Cathedral, where conservators resisted community pressure for full regilding and instead used reversible shell-gold inpainting [37].

After catastrophic fire or water damage, when original surfaces are largely lost or irretrievable, regilding may be proposed as the only way to restore legibility or function. This reflects a view of time-related damage – overpaint, wear, abrasions, and losses – as a disfigurement to be erased, rather than evidence of the history of an object [38].

The ethical cost, however, is exceptionally high. To recover a surface pattern, regilding commonly requires the removal of secondary layers – overpaints and earlier, often delaminating, regilding – as well as weakened original layers. This permanently destroys evidence such as the carat and thickness of the original gold leaf, the bole colour and composition, craquelure, and distinctive glazes or varnishes, all of which can reveal the object’s geographical origin, workshop practice, and age, as analytical technologies improve. Regilding can therefore have profound consequences. For frames, where centralized technical research on materials remains limited, such irreversible loss may prevent future reconstruction of framemaking history. Regilding therefore stands in direct conflict with the conservation principle of minimal intervention.

Original gilding was often finished with clear or pigmented varnishes to alter colour, protect the surface, or to imitate gold whilst using silver or tin. Over time, dust, soot, wax, and yellowed varnish forms a patina: a subtle coating integral to authenticity and aesthetic character. It softens glare, adds depth, accentuates carving, and records the passage of the object through time. Even cleaning therefore carries ethical weight, because these layers function as historical evidence of the intended appearance [39]. With original surfaces increasingly scarce, due to over-restoration and replacement, destroying this evidence erases history, authenticity, and artistry. Brandi and Philippot rejected complete regilding, favouring interventions which preserve the ‘golden stain of time’ and keep additions recognizable and reversible [40].

In-gilding

In-gilding is a more conservative approach, which balances visual reintegration with the preservation of original material. Unlike overall regilding, it treats only losses whilst leaving the surrounding original surfaces untouched or gently cleaned [41]. It aims to restore aesthetic unity without indiscriminate loss of historical evidence, although overpaints may still need removal [42].

Because gilded surfaces are often multilayered, examination must first identify which layers are original or otherwise worthy of preservation. In-gilding then rebuilds losses with gesso or synthetic fillers, bole or conservation-grade paints, and gold leaf applied by traditional or modern methods using synthetic emulsions or resins [43]. The new gold is then toned, distressed, and patinated to match colour, sheen, texture, and craquelure, all of which requires material knowledge, visual sensitivity, and artistic skills [44]. Done well, it improves legibility and coherence whilst preserving most original material.

Its main ethical dilemma is distinguishability. Conservation ethics require integrations to be identifiable on close inspection, so they do not mislead viewers or future examiners [45]. Brandi regarded mimetic retouching as historical falsification, and Baldini similarly warned that artificial priming and bole can create an arbitrary false ‘lifetime’ for an object [46]. Perfect in-gilding therefore risks becoming indistinguishable from the original, and if undocumented, it risks misleading future examinations.

Recent responses to this challenge include non-traditional gilding systems using conservation-grade synthetic polymers detectable by FTIR or other technical analysis [47], and traceable gold leaf (such as that developed by C2RMF with Dauvet Gold Beating Company). This leaf is visually and chemically close to traditional gold but contains minute amounts of non-native markers – like indium and/or palladium, detectable by pXRF – allowing aesthetic reintegration while preserving scientific recognizability [48]. Modified fills containing bismuth oxide, or barium sulphate in replacement ornament recipes, similarly remain visually compatible but identifiable by X-radiography, improving the documentation of repairs existing beneath the gold leaf [49].

In-painting (non-gold leaf compensation)

In-painting, or non-gold leaf compensation, is the most ethically established rigorous approach for treating losses on gilded surfaces. It reduces visual disruption and restores legibility without deceptively replicating original material, establishing the object as an authentic historical document.

In-painting generally falls into two categories: mimetic retouching, which attempts to match colour, texture, and gloss, and was rejected by Brandi [50], and visible retouching, such as tratteggio or rigatino, puntinato, ‘chromatic selection’, and ‘chromatic abstraction’. These methods are intended to integrate losses at normal viewing distance whilst remaining distinguishable up close, thereby reducing conservator subjectivity [51].

An example of tratteggio, glossary, Museu Nacional d’Arte de Catalunya

These approaches derive from Brandi’s theory of restoration and the work of Philippot with Paolo and Laura Mora, whose writings described tratteggio, developed at the Istituto Centrale del Restauro in 1945–50. The technique uses fine hatched lines in several tones to reintegrate losses while maintaining distinguishability [52]. Baldini later developed ‘chromatic selection’ and ‘chromatic abstraction’, explained in his two volumes of the Theory of restoration and methodological unity [53]. The practical aspects of the retouching techniques were described by conservator Ornella Casazza [54]. For compensation of losses in gilding, Baldini specifically developed a ‘gold selection’ method, in which yellow, red, and green strokes, or puntinato, create the visual effect of gold [55]. Philippot described conservation intervention as a ‘modern, critical act’, distinguished from craft restoration by non-falsifying integration [56]. Although first developed for mural painting, these principles now underpin retouching methodologies in gilded and polychrome wooden sculpture in many conservation schools [57].

Both in-gilding and in-painting depend on stable, compatible materials. Unstable brass powders have largely been replaced by reversible alternatives such as mica pigments, watercolours, gouache, gum Arabic, Funori, PVA, acrylics, Laropal® A81, and Paraloid B-72 systems [58]. Dye-tinted resins can imitate aged shellac glazes over silver or tin more convincingly than paint because of their clarity and saturation [59]. Crucially, retouching is usually applied over an isolation varnish such as Paraloid B-72, protecting original surfaces and allowing future removal [60].

High-gloss gilded surfaces remain difficult to simulate because paints and resins cannot fully reproduce the optical qualities of metal leaf. For this reason, in-painting is often recognised as an aesthetic compromise. Italian conservation practice developed a technique based on retouching, built up by varied subsequent layers; for example, an initial mica or gold-powder layer is followed by watercolour tratteggio or puntinato [61]. This method can improve integration whilst remaining distinguishable on close inspection.

Decision-making in gilded wood conservation is shaped by the tension between material authenticity and aesthetic integrity. Regilding sacrifices authenticity to restore an assumed or identified original appearance. In-painting prioritizes authenticity, reversibility, and optical integration. In-gilding occupies the middle ground, offering stronger aesthetic reintegration whilst preserving existing original material, but with possible compromises in reversibility and legibility.

The boundary between conservation and restoration remains subjective and challenging, since both require subjective assessment and interpretation. Financial constraints may also limit treatment to stabilization and preservation, excluding detailed retouching or in-gilding. Whatever approach is chosen, thorough documentation is essential for ethics, accountability, and future retreatment.

A proposed integrated decision-making framework for gilded wood conservation

Conservators have long recognized that no uniform guidelines can apply to every object; each requires its own evaluation and treatment strategy. The preceding analysis shows that choosing between regilding, in-gilding, and in-painting is not merely technical, but an ethical and philosophical decision shaped by the condition, context, and value of the object for those involved. In museum contexts, reconstructing losses in gilded polychrome sculpture is often avoided as excessive, interpretative, or potentially falsifying, particularly where exposed wood may contribute aesthetically and structurally to the work’s interpretation [62]. In contrast, filling and reconstructing gilding losses are generally accepted for frames, furniture, and architectural decoration [63]. Navigating these distinctions requires a systematic, transparent process which merits broader discussion in the conservation of giltwood objects.

The proposed step-by-step decision-making framework shown in Table 1 (above) is a synthesis of three established models, designed as a flexible yet rigorous guide for professional practice. By combining the principles of value-based management promoted by the Getty Conservation Institute (GCI), the risk assessment approach of the Canadian Conservation Institute (CCI), and the normative process model developed by the Dutch Foundation for the Conservation of Modern Art (SBMK), this framework provides step-by-step guidelines for the giltwood conservator, from initial assessment to a well-justified and documented treatment plan for gilded wooden objects.

Table 2 Integrated decision-making framework proposal for gilded wood conservation (click for larger version)

Application of the decision-making framework: A hypothetical case study

To illustrate the practical application of the proposed framework, the author applied the principles of the five steps, shown in Table 2, to a hypothetical yet representative scenario drawn from conservation experience, accepting for the purpose of this illustration the obvious simplification of the planned actions and omitting the common initial stages of conservation treatment (e.g., fumigation with low oxygen method, initial consolidation, preparation layers, infillings, etc.) and suggesting of any materials. The case study is as follows.

Hypothetical background information

Examples of two 18^th century picture frames. Author’s photo

A museum acquired a large painting by a notable 19^th century artist, housed in an elaborate carved and gilded frame dating from the 18^th century. The donor is a major sponsor, and the painting is understood to have remained in the family collection for many years. The painting itself is not addressed in this discussion.

The frame has visibly deteriorated, although an initial assessment by a preventive conservator suggested that it could be considered stable, since a continuous overpaint layer appeared to be consolidating the earlier finishes and the fragile substrate beneath. Its surface is dark and dull, and some ornamental elements show recent losses. A closer preliminary examination by a conservator experienced in giltwood conservation identified fragile, delaminating foundation layers beneath the overpaint, crude earlier repairs, and modifications to the moulding, presumably made to accommodate the painting.

Proposed decision-making framework and formulation of a treatment plan for the elaborately carved 18^th century frame

Examples of three 18^th century picture frames. Author’s photo

Step 1: Establish context and assess values

The process begins by identifying the significance of the frame, and the people involved, through records, literature, and the central question: why should this frame be preserved?

Its values may include:

• Historic value – although not original to the painting, the frame is an authentic 18^th century object which may preserve evidence of original gilding, materials, carving, and craftsmanship.

Its historic significance depends on when and why it was paired with the painting, whether by the artist, dealer, or a later owner, and whether it shaped the intended presentation of the painting.

• Aesthetic value – although it is currently unsuitable for display, the appropriate treatment could restore the legibility of the frame and its visual partnership with the painting.
• Artistic value – revealing the original carving and design beneath the overpaint may clarify the artistic qualities and workmanship of the carver and gilder.
• Functional value – the frame appears to fit, support, and protect the painting effectively.
• Scientific value – Its stratified finishes, potentially including 18^th and 19^th century layers, are important evidence, requiring technical analysis.

Curators, paintings and frame conservators, and the sponsor or donor should then review the evidence together, define treatment priorities, and, if useful, develop a shared ‘value pie chart’.

For the 18^th century frame, this ‘value pie chart’ is essential for ranking treatment goals and building a consensus of opinion amongst those involved. Weighting values – for example, awarding 35% aesthetic value and 20% historic value – recognizes the frame as both an 18^th century artefact and a visual partner to the 19^th century painting. It also justifies active intervention, such as overpaint removal followed by in-gilding or in-painting, because the current dark, overpainted state cannot meet the high aesthetic requirement. By making these priorities explicit, the conservator moves from subjective preference to a transparent, value-driven treatment goal.

Pie chart illustrating the distribution of values attributed to the 18^th century frame in this hypothetical case study

Step 2: Identify and analyse risks

 A thorough condition assessment is needed to identify the active threats to the frame and the scale of risk to its values. Visual examination should be supported by diagnostic analysis to clarify the stratigraphy and stability of the gilded surface.

Assessment should distinguish the original 18^th century materials from later 19^th century finishing campaigns associated with the pairing of the frame and the painting. Cross-section microscopy, solvent testing, FTIR for binders, SEM-EDX for compositional data, and preliminary cleaning tests can determine both the structure of the layers and whether the upper overpaint can be removed safely.

This analysis indicates that beneath the dull, continuous brass-based overpaint, the frame has suffered systemic deterioration, including a fragile wooden substrate and delaminating foundation layers.

The main risks are physical, chemical, and aesthetic:

Physical threats: Structural instability and gesso delamination threaten the survival of the original 18^th century reparure, punchwork, and carved ornament.

Chemical threats: Brass-based overpaint can react with binders to form copper carboxylates, producing green corrosion which may permanently alter the original gilding.

Aesthetic threats: Dark, unstable overpaint and missing ornament obscure the 18^th century carving and separate the frame visually from the 19^th century painting.

If left untreated, these risks would cause significant value loss:

Historic and scientific value would be diminished as corrosion and delamination destroy the original 18^th and 19^th century surfaces, evidence of craftsmanship, and material history.

Aesthetic and functional value would decline because the dull overpaint disrupts the relationship of frame to painting, weakens its quality in display, and undermines the supporting visual rôle of the frame.

Institutional and social value may also be affected, as continued neglect could suggest inadequate care, disappoint the donor, jeopardize future support, and reduce the perceived or monetary value of the artwork.

Step 3: Define treatment goals and ethical parameters

After defining the values of, and potential risks to, the frame, Step 3 sets the treatment objectives and ethical limits by balancing the competing demands placed on this 18^th century frame.

Although not made for the 19^th century painting, the frame functions as an authentic period frame if selected by the artist, dealer, or primary owner. It therefore preserves important evidence of 18^th century craftsmanship and gilding, as well as later 19^th century finishing campaigns, all of which require careful protection.

At the same time, the frame cannot be treated only as an archaeological relic. Following Philippot’s view of the artwork as a visually cohesive whole, its damaged, overpainted, and fragmented state disrupts the presentation of the painting and justifies remedial conservation.

The ethical task is therefore to mediate between visual coherence and respect for authentic marks of age in the frame. Any reintegration must restore aesthetic continuity without creating historical forgery [64].

These priorities establish the benchmark for later decisions: treatment should improve the visual cohesiveness of the frame with the painting, whilst preserving its historical integrity and retaining the original materials wherever possible.

Step 4: Evaluate treatment options

With the goals of treatment defined, this step assesses regilding, in-gilding and in-painting through risk-benefit analysis, weighing visual coherence against material authenticity, retreatability, and distinguishability. Table 2 presents a simplified set of options; in practice, many more variations might be considered.

Although inaction can serve as a risk baseline, it is unacceptable here: visual dissociation would remain, active delamination and brass-overpaint corrosion would continue, and the original 18^th century fabric would continue to deteriorate. Minimal intervention, such as replacing ornaments whilst retaining the dark overpaint, is also insufficient because it would not restore the aesthetic effect, nor satisfy the expectations of the donor. Overpaint removal is therefore necessary, followed by selection of an appropriate reintegration strategy.

Evaluating active interventions

Total regilding would produce a brilliant, cohesive picture frame but is ethically unacceptable, as it would remove weakened original layers along with the overpaint, destroying evidence of the 18^th century carving as well as 19^th century finishes, and breaching the requirements of minimal intervention.

In-painting, using stable and distinguishable resins or watercolours, best preserves both authenticity and reversibility, but may not reproduce the brilliance or optical effect of gold leaf sufficient for the display of the painting.

In-gilding offers the strongest compromise: if confined to the losses, it preserves surviving 18^th and 19^th century materials whilst restoring visual unity. Its risk of overly perfect, less distinguishable repair can be reduced by traceable gold leaf alloys containing indium or palladium markers, enabling future scientific detection.

A 3D-scanned digital twin can help compare the results of in-gilding and visible in-painting by simulating their visual effects before the intervention is carried out, reducing subjectivity and supporting the consensus of curators and donor.

Step 5: Propose, justify, and document the treatment plan

Step 5 formalizes the treatment proposal, after evaluation of the possible options and consultation with those involved, requiring transparent justification and future distinguishability of all modern intervention.

The proposed treatment is a careful removal of the disfiguring brass-based overpaint, followed by localized in-gilding or, depending on trials overseen by those involved, high-quality visible in-painting.

This approach satisfies the high aesthetic and functional priorities of the value pie chart, mitigates the risks identified in Step 2 by addressing corrosion and delamination, and meets Step 3’s ethical parameters by restoring visual coherence whilst preserving surviving 18^th and 19^th century materials.

Traceable materials must be specified so future conservators can distinguish modern repairs from original surfaces and avoid historical forgery.

The plan concludes with rigorous pre-, during-, and post-treatment documentation, including photography, stratigraphy mapping, and a distinguishability checklist recording chemical markers and synthetic binders. This creates accountability, documents the ‘critical act’, and allows procedural adjustments as the true condition of the underlying 18^th or 19^th century surface emerges.

Conclusions

Conservation practice will continue to evolve as materials sciences and digital analytical technologies advance, not by replacing core ethical principles but by giving conservators more refined ways to uphold them.

Further research may produce more stable, reversible, and optically convincing materials for in-painting, narrowing the visual gap between non-gold-leaf compensation and gilding.

Digital technologies may be especially transformative. High-fidelity 3D scanning and ‘digital twins’ make virtual conservation increasingly possible. Through VR or AR platforms, conservators and others involved could compare the effects of regilding, in-gilding, and in-painting before applying the physical treatment, improving communication, consensus-building, and informed decision-making.

Traceability may likewise become a standard requirement for conservation materials. If consolidants, adhesives, pigments, varnishes, and replacement gilding were designed with non-destructive chemical or isotopic markers, future conservators could identify modern interventions clearly. Such transparency would strengthen the ethical principle of distinguishability and make the treatments of today more accountable within the long material history of an object.

Ultimately, giltwood conservation is shaped by a persistent tension between material authenticity and aesthetic integrity. Regilding favours a perceived original appearance at the expense of surviving material evidence; in-painting prioritizes authenticity, reversibility, and optical reintegration; and in-gilding occupies a middle ground, offering stronger visual unity while preserving original material, although sometimes compromising reversibility and legibility. No universal hierarchy exists among these options. The most appropriate treatment must be determined through rigorous, context-sensitive analysis of the specific object. The proposed framework therefore supports transparent decision-making by helping conservators balance authenticity, aesthetics, function, the values of those involved, and ethical responsibility in contemporary giltwood conservation.

Malgorzata Sawicki

Independent research consultant; formerly Head of Frames Conservation, Art Gallery of New South Wales, Sydney, Australia (retired)

margaret.sawicki@gmail.com

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Acknowledgment

This article is loosely based on two lectures on the subject: a presentation delivered to the online ICOM-CC Documentation Working Group and the Wood, Furniture, and Lacquer Working Group seminar on ‘Collaborative approaches to documentation and decision-making in the conservation of wooden artefacts’ (6 December 2025), and the keynote address at the Frame: Concept, History & Conservation Symposium 3 (16–18 February 2026), Hobart, Australia.

It is also an abbreviated version of the author’s paper, ‘Decision-making in gilded wood conservation: A critical framework proposal for evaluating re-gilding, in-gilding and in-painting’, published in Studies in Conservation

ORCID

Malgorzata Sawicki

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References

[1] Jenner, 1994

[2] Cornu, 1986; Shelton, 1996

[3] Ibid.; ibid.; Sawicki, 2010, 2020

[4] Brandi, 1996a, 1996b, 1996c, 2005; Philippot, 1996a, 1996b, 1996c; Ciatti, 2003; Hughes, 2008; Valentini, 2008; Brajer, 2015; Meraz, 2019; Metzger, 2021; Cuzzolin et al., 2023

[5] Valentini, 2008; Spaarschuh and Kempton, 2020; Cuzzolin et al., 2023

[6] Appelbaum, 1987; Sawicki, 1995; Shelton, 1996; Robcis et al., 2016; Henderson and Waller, 2016; Streeton and Böhme, 2021

[7] Bomford, 1994

[8] Albertson and Murray, 2009; Henderson and Nakamoto, 2016; Streeton and Böhme, 2021

[9] Bomford, 1994

[10] Stoner and Verbeeck-Boutin, 2017; Tonini, 2021; Cuzzolin et al., 2023

[11] Muñoz‑Viñas, 2005

[12] ICOM-CC, 1984; AICCM, 1986

[13] AICCM, 1986

[14] Appelbaum, 1987

[15] Brandi, 1996c

[16] Thornton, 1991; Sawicki, 2002, 2006, 2010; Bajia, 2015; Aničić Eterović, Letilović and Tomaš, 2017

[17] Auffret, 2011

[18] Ibid.

[19] Ibid.

[20] Brandi, 1996; Brajer, 2015; Meraz, 2019

[21] Philippot, 1996a, 1996c

[22] Albertson and Murray, 2009; Henderson and Nakamoto, 2016; Streeton and Böhme, 2021

[23] Mora, Mora and Philippot, 1996; Albertson and Murray, 2009

[24] Sawicki et al., 2019; Tobin and Sawicki, 2026

[25] Sawicki and Rouse, 2016; Sawicki, Rouse and Limoges, 2017

[26] Philippot, 1996a

[27] Sawicki, 2020

[28] Johnson, 2025

[29] Mason, 2002; Henderson and Weller, 2016; Henderson and Nakamoto, 2016; Michalski and Pedersoli, 2016; Giebeler et al, 2019; Biasetti and de Mori, 2021

[30] Henderson and Weller, 2016

[31] Henderson and Weller, 2016; Biasetti and de Mori, 2021

[32] Philippot, 1996b; Burgio and Gregory, 2021

[33] Shelton, 1996; FLSY1, 2015

[34] Moyer and Hanlon 1995, 1996; Bajia 2015

[35] Belishki, 2018

[36] Philippot, 1996b

[37] Stein et al., 2000; Henderson and Nakamoto, 2016; Spaarschuh and Kempton, 2020

[38] Jenner, 1994; Shelton, 1996; Robcis et al., 2016; Streeton and Böhme, 2021

[39] Jenner, 1994; Sawicki, 1995; Shelton, 1996; Moyer, 2008; Robcis, 2016; Stoner and Verbeeck-Boutin, 2017; Streeton and Böhme, 2021; Cuzzolin et al., 2023

[40] Brandi, 1996a; Philippot, 1996a, 1996b, 1996c

[41] Sawicki, 2006; Bajia, 2015; Aničić Eterović, Letilović and Tomaš, 2017

[42] Moyer, 2008

[43] Thornton, 1991; Shelton, 1996; Sawicki, 2002, 2006, 2010, 2017; Moyer, 2008; Bajia, 2015; Aničić Eterović, Letilović and Tomaš, 2017

[44] Shelton, 1996; Ciatti, 2003; Moyer, 2008; Brajer, 2015; Bajia, 2015; Cuzzolin et al., 2023

[45] Tonini, 2021; Cuzzolin et al., 2023

[46] Baldini, 1996

[47] Thornton, 1991; Sawicki, 2002, 2010, 2017; Moyer, 2008; Bajia, 2015

[48] Robcis et al., 2016

[49] Thornton, 1991; Salimnejad, 2005

[50] Cuzzolin et al., 2023

[51] Samet, 1998; Ciatti, 2003; Mercier and Benati Rabelo, 2017; Severini, 2017; Tonini, 2021; Cuzzolin et al., 2023

[52] Brandi, 1996a, 1996b, 1996c, 1996d, 2005; Mora, Mora and Philippot, 1996

[53] Baldini, 1996; Ciatti, 2003

[54] Muir, 2010

[55] Baldini, 1996; Ciatti, 2003; Nicolaus, 1999; Sawicki, 2010; Cuzzolin et al., 2023

[56] Philippot, 1996b

[57] Albertson and Murray, 2009; Cuzzolin et al., 2023

[58] Sawicki, 2006, 2010; Bailão and Cardeira, 2017

[59] Tobin, 2021

[60] Cuzzolin et al., 2023

[61] Ibid.

[62] Serck-Dewaide, 1991; Philippot, 1970; Robcis et al., 2016; Spaarschuh and Kempton, 2020; Streeton and Böhme, 2021; Tonini, 2021; Cuzzolin et al., 2023

[63] Cornu, 1986; Serck-Dewaide, 1991; Jenner, 1994; Shelton, 1996; Bajia, 2015; Angeliki and Vasiliki, 2015; Robcis et al., 2016

[64] Philippot, 1996a; Fernandes and Murta, 2015