How to Write an Effective Specification for Gilding & Gold Leafing
Gilding is a truly ancient process, believed to have been first developed in Turkey over 8,000 years ago. The ancient Egyptians used it embellish the sarcophagi of pharaohs, the Phoenicians used it to plate less expensive metals to sell them for more at market, and more recently Europeans have used gilding to cover surfaces ranging from ceilings, wood frames, to dinnerware. While many of the processes to apply gold leaf are rooted in similar principles, the process has evolved greatly with time—which has made the process safe and ensures that the finish lasts longer.
When it comes to writing a specification, it is important to do a pre-project investigation to understand not only the scale of the needed gilding restoration, but also understand what are the underlying issues causing the gold leaf finish to fail. Is the project indoors or outdoors? What is the base material to which the gold leaf was applied? How was the gold bonded to the surface? Is that the most effective method?
Developing a baseline understanding of these key questions will ensure your conversations with prospective restoration professionals remains grounded. Additionally, we encourage prospective clients to do the following four things prior to starting any gold leaf project or specification:
Hiring a Restoration Contractor? This contractor checklist can be used as a tool to evaluate firms' experience and qualifications.
1. Understand the Gilding ProcessApplication methods change based on the material the gold leaf is being applied. These are a few of the most common types of gilding applications:
- Overlaying: this is the simplest form of gilding and is most likely the original form used in ancient times—references to this type are made in both Greek mythology and the Bible. Heated gold is hammered into thin sheets and then applied once cooled to the intended surface; note that the layer of gold associated with this process is significantly thicker than golf leaf which, was not invented until the Middle Ages. A layer of adhesive is applied to prepare the surface—most commonly it is a simple adhesive made from vegetation and/or animal bones. In ancient times, bitumen (asphalt) was commonly used as the adhesive.
- Water gilding: enables the gold finish to be mirror-like and polished in appearance. This process uses ground gypsum/chalk mixed with glue as a base coat. The surface is dampened and then buffed again with water.
- Oil-gilding: similar to water gilding, however, the surface is buffed with an oil to finish—typically linseed oil.
- Cold Gilding and wet gilding are process used to apply gold to metal surfaces; the former to sterling silver (vermeil finish) and the latter to more generalized metals.