Where Technology Is Taking Diamond Grading

Technology is enabling more precise, automated manufacturing and grading of diamonds that will ultimately improve consumer confidence.

Diamond grading is not an exact science. Indeed, of the four key grading criteria, only carat weight is a purely objective measurement. Color, clarity and cut are all, to one degree or another, a matter of subjective judgment. However, there are labs and technology companies working to get past the subjective nature of grading.

Technology is not only helping transform the accuracy of grading, it is making an impact across the entire distribution chain.

This work is being spearheaded by advancements in technology. This allows the analysis of colors D to Z, secondary hues, and fluorescence. It can also measure proportions of a cut and its light performance, and map internal characteristics using advanced optics, imaging technology, and computer programs that cross reference data to automate and integrate diamond grading.

Technology is not only helping transform the accuracy of grading, it is making an impact across the entire distribution chain. At the rough level, technological developments have enabled mining companies to automate many of the sorting judgements that were previously done manually. This has resulted in more accurate and effective categorization. Automatic industrial sieves have improved the weighing process, while newly developed automatic sorters can separate stones by shape.

REVOLUTIONARY

In manufacturing, advancements in technology have also revolutionized how diamond cutters determine the optimal polished gem. “The equipment out there provides an MRI of the diamond to tell exactly the way to cut the rough to get the best out of it,” says Ronnie VanderLinden, president of the Diamond Manufacturers & Importers Association of America. Such planning enables the manufacturer to obtain the optimal cut, considered by many to be the most important characteristic in diamond grading.

Cut determines the overall beauty of a diamond in terms of sparkle, fire and brilliance, says Antoinette Matlins, a gem and jewelry expert and author, based in Woodstock, Vermont. “It is the least understood but most important of the 4C’s and the one factor I won’t compromise.”

AUTOMATING COLOR AND CLARITY

Perhaps the biggest challenge lies at the grading level, which still requires human judgement to communicate the quality of a diamond. In particular, clarity and color remain the most challenging grading criteria to automate.

New equipment is under development to automate color and eventually clarity grading, but they still require final verification by a gemologist.

However, even as technology improves the accuracy and quality throughout the diamond mining, manufacturing and grading process, it is still unlikely to replace the final inspection it receives before a sale is made. “In that last 18 inches of the sale, the final vote comes down to the human eye and what attracts it,” assures VanderLinden.

And ultimately, while technology will always add value, it will always be that law of attraction that fuels the diamond industry.