The ‘ cut' or ‘ make' of the stone affects both the overall attractiveness and personality of the finished product. It does not refer to the shape of the stone, which can be shaped in various ways. The proper proportion for cutting is usually the stones crown being roughly a third of the pavilion depth. This is particularly important with diamonds, as their fire and brilliance is almost wholly dependant upon the skill with which it was proportioned and finished. Shoddy cuts will ruin the stone's symmetry and the only possibility of realignment would be to lose a huge amount of material and thus carat weight. This is the singularly most important factor in a diamonds ultimate market value, because cutting can either make or ruin a diamond forever.

A stone that has been poorly cut can never be refined again- the various cutting styles determine the removal of rough material that are lost forever in the process and it can also adversely affect the clarity of the stone. Wrong cutting makes the stone vulnerable to chipping or the emergence of fine cracks. This is the main deciding factor in the quality of any mounted diamond; - the finest-cut diamonds in the world may have lost a great deal of their primary weight in the cutting process, but the fine precision and long hours that went into it's making still place it as the more expensive stone.