This is probably a long shot but does anyone know anything about dealing with bleached out colours on natural rugs (not sure if it's sisal or seagrass). A friend of mine cleaned up a spill on a large custom natural rug in an apartment they had been put up in on moving to a new city, new job. The spill removed but the colour started to come out of the rug where it has been cleaned.

Is there any products out there for blending the colour back? Chalks, or dyes or paint?