Xexliftbecause some of the atoms in the diamond's crystal structure have now been dislocated and this in turn has affected the way light passes through the diamond. Next the diamond goes through a controlled heating (annealing) process, this allows some of those atoms to relocate (partially repaired) in order to obtain a desired color. Process #3- Coated Color Enhanced Diamonds- The coating on polished diamonds refers to a thin artificial layer that alters the color of the diamond. The coating can either be of the desired color or can cause a colored interference-effect.  

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