At a meeting on undisclosed synthetics in 2016, GIA chief laboratory and research officer Tom Moses lamented that people knew exactly what they wanted in a lab-grown diamond detector. “A black box,” he moaned. “For about 100 bucks. Sits on your counter.”
Since then, the number of man-made diamonds being produced has only increased, as have the chances of those diamonds being sold undisclosed. For jewelers looking to protect the integrity of their supply, the need for a cheap, easy-to-use synthetic sniffer is more pressing than ever. The good news is there are now many devices that help detect lab-grown diamonds. The bad news: A lot of them cost a decent chunk of change. So far, the dream of a $100 black box hasn’t come to pass.
Still, a few years back, there was considerable doubt over whether such a device was even possible. Now there are so many gadgets on the market that Signet and the Diamond Producers Association are working on an initiative that will make sure every device is up to snuff—to test the testers, so to speak.
Below is a sampling of the leading lab-grown diamond testing devices on the market. Most synthetic detectors check to see whether the stone is a type Ib or IIa diamond, as just about all synthetics fall in those categories. Lately, however, some of the more high-profile device makers, such as GIA and De Beers, have refined this approach, and their machines now look for other distinguishing characteristics. De Beers’ SYNTHdetect doesn’t look for diamond type at all.
Yet most of these devices aren’t technically detectors; they’re screeners. They can’t tell you if a stone is definitely lab-grown, but they can assure you that a stone is natural or warn that it needs further testing. That means some natural stones will end up “referred,” though some machines boast a lower false positive rate than others.
Alrosa Diamond Inspector
Developer: Alrosa Technology, a division of Alrosa
What it does: Screens stones for synthetics, treatments, and non-diamond imitations (simulants) such as cubic zirconia and moissanite.
Who it’s targeting: Produced by the prominent Russian diamond miner, it is meant for anyone in the trade, including manufacturers, pawnshops, jewelry retailers, and gemologists.
What’s unique about it: Uses three optical detection methods, which give its assessments high reliability, according to Alrosa. It can examine mounted stones, it’s portable, and it’s lower priced than others (if not exactly cheap).
(Automated Melee Screening)
Developer: International Institute of Diamond Grading & Research, a division of De Beers
What it does: The sequel to the first AMS, this second-generation model can screen up to 3,600 stones an hour—including round brilliants (from 0.0032 ct. to 0.2 ct.) and many fancy cuts (from 0.01 ct. to 0.2 ct.)—for synthetics and simulants.
Who it’s targeting: Users who either polish or purchase large volumes of melee, meaning diamantaires, jewelry manufacturers, and large chain retailers.
What’s unique about it: While De Beers freely admits that other devices can screen melee faster, it says the AMS2’s low referral (i.e., false positive) rate for naturals is “the best in the industry”—which means that it ultimately saves money and time. In addition, it can be loaded with 500 cts., and then be left overnight to process them.
(Automated Spectral Diamond Inspection)
Developer: Swiss Analytical Testing Tools, a division of Swiss Gemmological Institute SSEF
Price: 350,000 Swiss francs (about $349,000) for standard option
What it does: Screens colorless natural melee-size diamonds, referring CVD (chemical vapor deposition) and high pressure/high temperature synthetics and possible HPHT-treated diamonds. Can handle round stones from 0.85 mm to 3.8 mm in diameter, at a rate of 10,000 stones an hour.
Who it’s targeting: Intended for industrial application, in particular Swiss watchmakers.
What’s unique about it: Aimed at a very particular market. Also includes an option (for more money) that lets you sort stones by size into 14 different customizable measurements.
Developer: Gemological Institute of America
What it does: Examines unmounted D-to-N colorless diamonds (from one-pointers to 10 cts.) and flags them if they are treated or synthetic.
Who it’s targeting: The general trade.
What’s unique about it: Can examine a wide range of sizes. Unlike some of the devices here, also checks for possible HPHT treatments.
DiaTrue C Series
Developer: Ogitech Inc.
Price: $3,800 (DiaTrue CS); $8,000 (DiaTrue CM); $9,700 (DiaTrue CL)
What they do: DiaTrue CS screens synthetics and moissanite in small parcels of melee or rings. DiaTrue CM has a 50 mm tray and screens melee stones, rings, earrings, and small jewelry. And DiaTrue CL has a large tray and can screen jewelry combinations, melee parcels, and loose diamonds.
Who they’re targeting: The general trade.
What’s unique about them: Among the lowest-priced devices on the market.
Developer: Gemological Institute of America