The extracted dye from the dried fruit hulls of mangosteen was used as a natural dye for the dyeing of cotton and
silk yarn. The optimal conditions for dye extraction were to extract the dried fruit hulls of mangosteen at 80 oC for 1 hour
with a 15 % w/v citric acid solution in a 1:4 ratio of mangosteen powder to solvent. Cotton dyeing with the extracted dye
from the dried fruit hulls of mangosteen was carried out at 60 oC for 60 minutes with a material to liquor ratio of 1:25. The
effect on dyeing of mordant type with different mordanting methods was studied. The results showed that the dyeing of cotton
using the post-mordanting method with ferrous sulfate and calcium hydroxide not only provided better depth of shade but
also provided better wash fastness and light fastness than with other mordants (alum; zinc tetrafluoroborate) or without a
mordant. Good fastness properties were also obtained using a post-mordanted silk with calcium hydroxide.