Applying Gold Leaf
The gold leaf on most of our organs is applied using an old technique called "water gilding." In this method, the piece to be gilt is covered with multiple smooth layers of very fine clay mixed with a water based adhesive. After the layers are dry and the surface made smooth, water is applied using a fine brush. Pieces of gold leaf are then positioned in place, and air currents and the surface tension of the water pull the gold into place. Once the water has evaporated the surface is burnished with an agate. The result is a surface that is highly efficient at reflecting light. There is no good substitute for this method, but it is timely and costly.
Below is a short slide show of the steps involved.
