Lefranc Gilder’s Clay Base—also known as bole—is a red clay-like substance. It is applied to the prepared surface, which is usually Gesso. Gesso is a mixture of chalk and Glue. The gilder’s clay layer and the underlying layer of Gesso create a suitable layer that allows the polishing of gold leaf with the Agate Burnisher Stone.
One must know that the gilder’s clay base can only be used on absorbing surfaces.
How to prepare Lefranc Gilder’s Clay Base:
- Before using Lefranc gilder’s clay base, it has to be prepared with rabbit skin glue before it can be applied. This clay is already processed with water to a paste, but you need to add some Rabbit Skin Glue to it first.
- Normally, one part gilder’s clay and two parts rabbit Skin Glue (liquid form) depends on how thick or thin you want your clay to be.
- The rabbit skin glue must be warm when adding it to the gilder’s clay. Mix gently not to create air bubbles and until the texture is consistent, runny and smooth.
- For best results, apply two to three thin coats of this clay onto a perfectly smooth surface, such as Gesso.
- After the clay has dried, polish the clay with the Steel Wool Pad or with the Fiber Clouth to a perfect state. Your clay at this point must look clean, shiny, smooth and free from dust.
- Prepare the gold leaf water using the rabbit skin glue tablet or use a pre-made Kolner Colnafix Gilder’s Size. This mixture will make the clay surface a little wet for the gold leaf to stick.
- Apply the gold leaf, and let it dry for at least 5 hours.
- Your gilded surface is now ready to be burnished with the Agate Burnisher Stone.
- Buff any gold flakes that sits on the surface with the Gilder’s Wool Brush.
- Normally, 24k gold leaf does not need to be varnished to protect it from oxidization. However, for less than 24k, use Kolner Leaf Protect Varnish to seal the surface.