The substance used for decolorization of undesirable color in a crystalline substance is powdered animal charcoal
Decolorization is the process of eliminating organic contaminants with vivid colors from the sample mixture.
Unwanted colors are removed by boiling the item with a suitable amount of powdered animal charcoal in a hot solution that has been filtered so that the charcoal may absorb the colors. The charcoal is a finely divided carbon.
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