Egg tempera has been used since Roman times. It was widely used by the renaissance painters but was ultimately replaced by oil based paints which can be dispensed from a tube. Recently it has been gaining popularity again as artists discover the special characteristics of the medium which cannot be replicated by other forms of paint. xx
The materials are ground pigment, separated egg yolk, and water mixed into paint as needed. For me, grinding the pigment and mixing the paint adds to the satisfaction and enjoyment of the process. The painting surface is a traditional gesso ground (chalk mixed with gelatine solution) on a rigid panel. I use MDF boards as they remain rigid and stable even when the gesso is applied.
Once applied the paint dries immediately so the image must be built up in layers of fine brush strokes, giving it special qualities of colour and texture. It is not a quick process but is one that produces a refinement and intensity that is not easy to achieve with other forms of paint. More information about egg tempera and work by other artists can be found on the Society of Tempera Painters.