Sawing the crystals is a mechanical process accomplished by attaching the rough diamond to a mechanical arm and lowering it onto a high-speed rotating phosphor bronze blade in perfect alignment. This alignment of diamond and blade is guaranteed by the marking phase described in the previous paragraph.
The thickness of the blade and the amount of pressure that is applied is precisely calculated by the weight of the individual diamond and adjusted accordingly. The sawing benches are constructed of a special combination of composite materials for the sole purpose of removing vibration- thus more precision.
Regular diamonds take about four hours per carat to saw – however, the extra attention to detail takes Hearts On Fire diamonds six hours per carat to saw.