Gilding and Egg Tempera
These combined art forms, which date back to Egyptian and Byzantine times, have a close association with nature through the transformation of earthly materials and alchemy. In European medieval panel painting the use of gold leaf and egg tempera (pigments bound in egg yolk) reached its zenith in the 14th and early 15th centuries. The Wilton Diptych dated about 1395, housed in the National Gallery is a stunning example. Recipes contained in a 14th century treatise by Cennino Cennini remain relevant today.
Although gilded and painted icons provide a continuous link from the earliest Christian times to the present day, generally egg tempera was gradually supplanted by 'oil paint' and by 1600 virtually all great paintings were executed in oil. For 300 years egg tempera painting lay largely dormant until a revival in the early 1900's.