During recrystallization, an orange solution of a compound in hot alcohol was treated with activated carbon and then filtered through fluted paper.

During recrystallization, an orange solution of a compound in hot alcohol was treated with activated carbon and then filtered through fluted paper. On cooling, the filtrate gave gray crystals, although the compound was reported to be colorless. Explain why the crystals were gray and describe steps that you would take to obtain a colorless product.