Burial-induced color changes in unmordanted and mordanted madder-dyed fabrics were studied and characterized. Cotton and wool samples were pre-mordanted with five common mordants (aluminum, copper, chromium, iron, and tin), dyed with madder, and buried in moist sandy loam soil at 28°C for one to six weeks. Periodically samples were removed from the soil, and the colors of the samples were measured in CIE color coordinates. Color differences between samples were measured to determine the effect of mordanting and burial on the shade and depth of shade of the madder-dyed cotton and wool fabrics. Analysis of metal ions present in the dyed samples was carried out using x-ray fluorescence to determine the degree of mordanting that had occurred and the effect of burial on the metal content of the fabric samples. Burial of the mordanted and unmordanted dyed samples caused significant and progressive change in their shades and depths of shade. Chromium, copper, and iron mordanting was much more effective in preventing color change in the dyed cotton and wool samples during burial than aluminum and tin mordanting or no mordanting of the samples. Extensive metal exchange and uptake of iron was found in the buried samples. -- AATA