This research work involves the dyeing of wool with Marigold as a source of yellow colour. To do this, wool yarns
pre-treated with Alum as a colorless mordant, dyed with Marigold and then treated with different percentages of ammonia
solutions. The chromaticity co-ordinates of samples measured in CIELAB system. The L* values of all ammonia treated samples
decreased and the values of a*, b*, C* dependant on the ammonia solution. It can also indicate that the reflectance spectrum
of treated samples decreases due to ammonia treatment. The rate of vertical wicking decreases on Marigold dyed treated
with ammonia. Color hue of the Marigold dyed wool alters after washing with standard soap and ammonia after-treatment
has no influence on washing fastness. The samples dyed with Marigold and after-treated with ammonia show a lower light
fastness.