GIA Tests Cut Grade Software, Sarin’s Facetware Scores High

An in-depth comparison by the Gemological Institute of America (GIA), between their internal methods to determine the cut grade of a round diamond and Sarin’s new implementation of the Facetware database, shows highly compatible results between the two methods, according to Sarin Technologies Ltd.

To evaluate compatibility, GIA measured more than 14,000 stones, randomly selected during their diamond grading processes at various geographic locations, using Sarin’s DiaMension platform with version 5.0 of the DiaVision software. The measured data were processed twice – once by the GIA’s internal software and once by Sarin’s software.

Comparison of the results showed that 99.8 percent were identical for the proportion-based and brilliancy-variation aspects of the cut grade evaluation, a significant improvement over cut grade estimates from previous versions.

In addition, prediction of the effect on the cut grade from girdle minimum and maximum and culet size showed 98 percent agreement with reported descriptions of these parameters.

GIA introduced a new standard for cut grading of round brilliant diamonds in 2006 and uses a proprietary software package to assess it — a combination of proportion data measured by Sarin’s DiaMension, an analysis of variations affecting brilliancy (also called painting or digging out), and other visually evaluated parameters - polish, symmetry, girdle minimum and maximum and culet size.

Sarin has recently completed improvements to the implementation of the optional Facetware package in its DiaMension and DiaVision products to exactly match GIA’s methodology for calculating the proportion parameters, evaluating the brilliancy variations, and predicting the girdle and culet sizes.