The Fayum portraits have been primarily found in the Fayum area of Egypt. They date back to the Roman period, spanning the 1st through the 3rd or 4th centuries. The portraits were painted using either encaustic or egg tempera paints. These portraits, which were painted on wooden panels, were found on the caskets of prominent military personnel, civil servants and other dignitaries. Based upon the evidence, it is unclear if the persons depicted are Egyptians, Roman or Greek in descent. This is largely due to the paintings being poorly excavated and cataloged when they were discovered by early archaeologists.
Fayum portraits were painted primarily using the encaustic technique or sometimes egg tempera in later portraits. According to "An Artist's Handbook" by Margaret Krug, the word encaustic comes from the Greek "enkaustikos" meaning "to burn in." The ancient painters of the Fayum portraits would mix dry pigments with molten wax. This mixture would then be applied to a wooden panel. Using a soft cloth, the portraits could be shined to a dull sheen.
This painting method provided a durable medium that has lasted over 2,000 years. Pure encaustic paints, which used only wax, tended not to yellow because of an absence of oil. While the earliest portraits were mixed with only wax, the later ones tended to be combined with some oil, which explains the yellowing of later portraits.
Later Fayum portrait painters sometimes used egg tempera, a painting technique combining paint pigments and egg yolks, which act as a binder for the paint. The earliest record of this technique dates back to the 1st century A.D.
The paintings have been found primarily in the Fayum Oasis of Egypt, a land lying between a desert Oasis and the main Nile Valley. However, the classification of the portraits is actually based more upon style rather than geographic region. Because of the dry desert heat, the mummies are well preserved.
Fayum portraits, along with artifacts found in Herculaneum and Pompeii, are among the best preserved examples of art from the ancient age.