Agate Flat Burnisher number 39 with wooden handle. Burnishers are used as part of the Water Gilding technique of applying gold leaf onto surfaces carefully prepared with gesso and clay bole. Burnishers for Water Gilding are traditionally made from agate or animal tooth.
The clay bole is smoothed to a high finish before painting with a rabbit skin glue size. The delicate gold leaf is then placed over the tacky surface with a brush called a Gilders Tip and a Tamping Brush is used to gently press the gold leaf into place and dust away any flakes (skewings) that have not adhered. When dry, the gilded surface is then firmly rubbed over with the burnisher to compact the bole and produce a mirror shine.
This process is intended to simulate solid gold and preparation of the surface is essential to ensure that the burnishing process does not cause rips or tears in the gold leaf due to rough patches in the bole or contamination from dust particles.
Agate burnishers are also used for burnishing the surface of fired Art Clay Silver clay. The dried Art Clay Silver clay must be prepared very carefully to remove flaws before it is fired. Burnishing compacts and smooths the surface of the silver and gives a mirror like finish. Approx. length 22 cm. Agate tip 3cm wide