Ceramic & Sculpture Repair Lessons
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Why Painted Gold in Ceramic Repair & Restoration Cannot Match Precisely Kiln Fired Gold
Seamless restoration of pottery with gold-glazed details is one of the greatest challenges for conservators. When repairs are required, restorers apply cold gold paints to the repaired areas in an effort to restore the original gold details. While skilled application can achieve a close match in color and sheen, painted gold can never fully replicate the brilliance of kiln-fired gilding made with gold chloride.
 
The Science Behind Fired Gold vs. Painted Gold
Gold Chloride Gilding and Firing
Traditional ceramic gilding is achieved with a gold chloride-based solution (often called liquid bright gold), applied to already glaze fired ceramics and fired a second time for the gold colors.
- Medium: Gold chloride dissolved in oily resins (e.g., lavender oil).
- Firing Temperature: ~700–800 °C (1290–1470 °F).
- Reaction:
AuCl₃ → Au (metallic gold) + Cl₂ (gas)
- Result: A fused, continuous, mirror-like layer of metallic gold permanently bonded to the glaze.
Painted Gold in Restoration
In restoration, gold paints or powders are applied directly to repaired areas at room temperature.
- Composition: Finely ground metallic pigments (often real gold powders or imitation metallic pigments) suspended in a binder such as resin, varnish, or epoxy medium.
- Application: Brushed or airbrushed onto the surface in thin layers.
- Curing: Dries and hardens at ambient temperature, no firing is possible because adhesives and fillers in restored pieces cannot withstand heat.
Result: A reflective surface, but one made of microscopic pigment particles rather than a fused metallic film.
Optical Qualities
- Fired Gold: A smooth, continuous metallic surface that reflects light brilliantly, creating a liquid-metal effect.
- Painted Gold: Whether brushed or airbrushed, painted gold is composed of countless microscopic pigment particles and dots. Under close inspection, or under magnification, these dots are visible. This fragmented surface scatters light, producing a finish that is less reflective, less smooth, and lacking the depth and brilliance of fired gilding.
Why Restored Pottery Cannot Be Refired
It may seem logical to attempt refiring with gold chloride to reproduce the original brilliance, but this is impossible in restoration. Repaired ceramics rely on polymer-based materials, such as modern adhesives, fillers, and reinforcing compounds, that are only stable at low temperatures, typically up to ~200 °F (93 °C).
The 700–800 °C (1290–1470 °F) required for gold chloride gilding would cause these polymers to burn, char, or completely disintegrate, destroying both the repair and the artifact. For this reason, refiring a restored piece is never an option.
How Lakeside Pottery Studio Achieves the Best Possible Results
At Lakeside Pottery Studio, we understand the challenge of matching the unique brilliance of fired gold chloride gilding. While painted gold cannot equal kiln-fired gold, our techniques are designed to achieve the closest possible match in color, sheen, and reflectivity
- Careful Color Matching
We use a selection of high-grade restoration paints, each formulated to represent a different gold karat tone. These can be mixed in precise ratios to create a wide range of shades, allowing us to closely match the original gilding.
Sylmasta Ultimate Gold Paints
- Layering and Burnishing
Instead of applying a single coat, we build up multiple ultra-thin layers reducing the dot-like structure typical of painted gold. This creates a finish closer to the mirror-like effect of fired gilding.
- Airbrush Application
When appropriate, airbrushing produces smoother blending and a more even surface compared to brushing, reducing visible strokes and helping repairs transition seamlessly. However, airbrushing is not always possible. For example, when working on precise details such as thin lines or tiny decorative dots, brushing remains the only option.
  
- Protective Finishes
We apply conservation-grade coatings that enhance depth, improve reflectivity, and protect the restored surface from tarnishing or dulling.
- Setting Realistic Expectations
Even with the best techniques, painted restoration gold cannot match the liquid-metal brilliance of fired gold chloride. However, our results are often so close that only very careful inspection reveals the repair.
Materials: Mostly Sylmasta Gold Paints
To achieve the most authentic look possible, we use Sylmasta Ultimate Gold Paints, professional restoration pigments formulated specifically for conservation.
The Three Primary Sylmasta Golds
- Yellow Gold - Bright, warm tone (resembles 22–24K gold).
- Red (Rose) Gold - Rich, copper-tinted (18K effect).
- Pale (Greenish) Gold - Cooler, lighter tone (14–16K effect).
Custom Blends
- Yellow + Pale → ~20K effect (lighter, more neutral).
- Yellow + Red → ~18K effect (warmer, deeper).
- All three combined → customized tones for specific pieces.
Because the color of fired gold chloride varies depending on formula and kiln conditions, this flexibility in mixing is essential for accurate restoration.
Conclusion
Painted gold in restoration is a respectful compromise. It restores the artifact’s integrity and brings back its beauty, achieving a finish that is as close as possible to the original fired gold. Yet it will always appear slightly softer and less reflective than true kiln-fired gold chloride.
That said, we view the results through a critical, professional eye. A casual observer, however, will usually find it very difficult to see the difference.
For this reason, collectors and clients should understand: gilded ceramic repairs can be beautiful and sympathetic, but they will never be completely indistinguishable from the original fired gold glaze.
Appendix: A Historical Note on Kiln-Fired Liquid Bright Gold
The use of gold chloride dissolved in oily resins, commonly lavender oil, emerged in 19th-century European porcelain workshops, particularly in France and Germany.
This kiln-fired “liquid bright gold” technique became the standard in Meissen, Limoges, and later English porcelain factories. The resin ensured smooth application and then burned away in the kiln, leaving only pure gold fused into the glaze.
Modern formulations still follow the same principle, and the mirror-like brilliance they achieve remains impossible to replicate with cold-applied paints used in restoration today.
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