It takes years of training to cut Tanzanite to the point that it can be certified as an ‘excellent cut’, where the stone reflects light to create maximum brilliance. The process of cutting plays a crucial role in displaying the true colors of the gemstone and due to its ability to show either blue or violet from different angles the cutting direction determines the gem’s overall face-up colour.
One of tanzanite’s properties is that, a rough piece of Tanzanite on average only yields 25% of usable material so there is enormous pressure on the cutter to ensure that he can maximize return by choosing the best shape, whether that be a simple cabochon, or a more elaborate trilliant or a princess cut.
First, the stones are mounted onto ‘dop sticks’ and then the facets are cut and polished over the entire surface of the stone using a highly- symmetrical pattern.
The dop stick is inserted into a handpiece that allows precise control over the positioning and the facets are then ground, sanded and polished on a rotating lap containing ground diamond, while water acts as a coolant.
When one side (top or bottom) of the stone is finished the stone is then transferred to another dop stick, and the process repeated on the other.