This paper describes the treatment and conservation of the polychrome wooden coffin for the
unknown mummy of the late period that was in Saqqara stepped pyramids` stores. It suffered
from aspects of damage represented in damaging into large fragments, infecting by microorganism,
accumulation of dusts and cracks that are varied in shapes and sizes in the
different layers of painting. The components of the polychrome wooden coffin were studied
through investigation and using various analysis methods such as X-Ray diffraction (XRD),
Fourier transform infrared spectroscopy (FTIR), light Optical microscope (LOM) and Scanning
electron microscopy with energy-dispersive analysis of elements (SEM-EDX). The results
indicated that the type of the coffin wood is Cypress (Cupressussempervirens), and there are
five types of fungi that had been grown on it. They are Aspergillusniger, Aspergilusflavus,
Alternaria alternate, Emericella nidulans and Penicillium steckii. The ground layers consisted
of two layers; coarse layer (clay plaster) and finer coat (lime plaster).The black, pink, and
yellow pigments consisted of Pyrolusite, Hematite mixed with Gypsum and Goethite
consecutively. The medium color was animal glue. Therefore, the current study included
making conservation and maintenance of the coffin, mechanical and chemical cleaning,
fixation of the paint layer flakes, facing (surface protection), sterilization, reinforcement...etc.