There is a product called WHINK. Its sold in grocery stores, Walmart, etc. Its in kind of a bronze/brown colored bottle. Ive never tried this yet on colored material, but I have used it on white, and off white antique doll clothes, and antique cloth doll bodies(muslin, cotton,etc). I unstuff the body(very important!), remove the head & limbs if possible(if its not possible, just be careful to not put it on the face, arms, or legs) I wear rubber gloves(important!), lay the item in the bottom of the bathtub and carefully drip/squirt Whink on the rust area. You might have to do it more than once, but you will literaly see the rust stain disappear before your eyes. Then completely rinse this area with water. I also squeeze the material in some gentle soapy water(holding the limbs, etc out of the water if they werent removed), and rinse again. Ive been able to remove the rust stains caused by the cryer boxes on antique composition cloth doll bodies with no damage at all to the material. Note-read all instructions on the bottle. Ventilation is important.