How are lab-grown diamonds cut and polished?

Lab-grown diamond cutting is the process of shaping a rough, reactor-grown crystal into a faceted, polished gem using the same techniques applied to any diamond. The process begins with cleaving or sawing to divide the rough crystal into workable pieces sized for individual stones. Bruting follows, grinding the girdle into the target outline, whether round brilliant, oval, or another shape. Faceting runs in two phases: blocking establishes the table, culet, and main bezel and pavilion facets, then a second pass adds the star, upper girdle, and lower girdle facets, bringing a round brilliant to its full 57 or 58 facets. After inspection and any corrective polishing, the stone is boiled in hydrochloric and sulphuric acids to strip residual dust and cutting oils. The finished stone is then graded by IGI, whose report documents cut grade alongside the other quality parameters. Cut quality affects light return more than any other single factor, so it warrants close attention when comparing stones.