Will AI Replace Diamond Graders?
February 23, 23
There are no absolutes in diamond grading. It's like any job in the world that relies on people making judgments. There will always be differences of opinion, borderline cases, bad days, irritable people and human error. Different labs may well give the same stone a different grade. Sometimes the same lab will give it a different grade on re-submission
So it'll come as no big surprise to those in the industry that there were discrepancies between labs when the Canadian TV station CBC did an undercover investigation. The focus of the story, by the government-funded broadcaster, was on jewelry retailers "deceiving" customers, but ultimately the labs took the blame.
The report claimed diamonds bought from three popular chains - Peoples Jewellers, Ben Moss Jewellers, and Michael Hill - were over-priced because the gradings were too generous.
The diamonds were sold with certificates from GSI and IGI. The TV station sent the stones to be re-graded by GIA, presenting its results as "right" and the other labs as "wrong".
The CBC report didn't provide much in the way of 4C detail, but concluded that prices had been inflated, as a result, by as much as 23 per cent.
Journalists are experts for the afternoon in any given subject. They focus on the facts and figures that provide a great headline. But the devil's in the detail, and in the background. And very often they don't have the time or inclination to delve too deeply.
Roland Lorie, CEO of IGI, described the story as biased, subjective and unprofessional. "A fair study would ensure anonymity, with neither side knowing grades of the other," he said, noting that GIA would have known from the laser inscription how the stones had been graded by another lab.
"One-grade differences happen and are tolerated in the industry. There is no evidence whose grades are incorrect, yet the journalist decided alone who was right, when in fact they were both stricter or softer."
Maybe there's another way. Will there come a time when AI completely replaces human diamond graders? No, says Lorie (who runs a grading lab). Yes, says David Block, who runs a diamond tech company (he's CEO of Sarine).
Lorie believes there will always be a need for human input. "We believe AI has a future in color grading, for certain, and likely for clarity," he said. "The results of IGI's R&D are promising. In fact, AI should be possible for a majority of stones.
"However, many will remain a challenge because AI requires hundreds of thousands of inputs. There are simply not enough samples of everything, certain tinges for example.
"At IGI we believe AI can help much of the time but human judgment will still be needed at the end."
Block disagrees, and sees a time when AI will do it all. "Automated technology-based grading will take you all the way, eventually, with all parameters," he said. "And I've no doubt about that. I'm sure, 100 per cent."
"I would say today, quite confidently, that I believe that grading of the 4Cs is done better by technology than manually."
He said AI is "dramatically" more repeatable than manual grading, which means it will always grade the same stone the same way. But it learns accuracy from manual graders, and will take time to iron out their inconsistencies. That's why he emphasized "eventually".
Today's technology today can already grade color, fluorescence, clarity, cut grade and symmetry in a consistent way, he said. In the near future, it will include polish quality, tinges, milkiness and more.
Have a fabulous weekend.