Icon painters describe their work as writing an icon rather than painting one, a distinction that signals the process is understood as following a received pattern rather than as free artistic composition.
Materials and method
An icon is built on a wood panel, traditionally linden or cypress, first covered with linen cloth glued down and then several layers of gesso sanded smooth. The image is painted in egg tempera, pigment bound with egg yolk, applied in a fixed sequence from dark underpainting toward lighter highlights, with the background frequently covered in gold leaf applied over a red clay ground called bole and burnished to a shine. This sequence is taught and repeated rather than improvised, which is part of why icons across centuries and regions resemble one another so closely.
Who writes one, and what happens to a damaged icon
Traditionally an iconographer is a monastic or a lay painter trained within that discipline, often undertaking prayer and fasting before beginning a new icon, with major centers of production historically including Mount Athos and, more recently, dedicated icon painting schools training laypeople as well. Any icon may be venerated by the laity once completed, kissed and honored with incense, without restriction on who may pray before it. A damaged icon is not thrown away, it is restored where possible, and where it cannot be, Orthodox custom in some regions has it burned or set afloat on water rather than discarded as ordinary refuse.