The International Gemological Institute (IGI) has added the cut grade to its fancy-shape diamond reports. In addition to the traditional analysis of polish and symmetry, the institute is now assessing the influence that cut quality has on the light behaviour in shapes other than round.
The reason for this is that, while the performance of a round can be decisively predicted by knowing its measurements, with fancy, on the other hand, the performance of the light cannot be predicted with the proportions due to its greater complexity, IGI explained.
To overcome this problem, IGI devised a four-step system that combines proportion requirements with visual evaluation.
For many decades, Carat, Colour and Purity have been the main focus for consumers when approaching diamonds. With the growth of e-commerce, more and more professionals and consumers are relying on grading reports to obtain in-depth and objective information on all four Cs of a diamond’s value, before they have even seen it.
At the same time, the range of available shapes has also increased. IGI CEO Roland Lorie described the urge behind the institute’s decision, which is based on estimated data revealing that the past few years have seen an increasing focus on cutting, first with rounds and now with fancies.
On 13 September 2022, a webinar with Rapaport on fancy diamond cut quality assessment, “Fast-Tracking the Future: The Shape of the Fancies Market”, was presented for the occasion. Experts analysed the important topic of grading, asking why it is so difficult to assess cut quality for stones that are not standard round brilliant.
