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Most jewelers are honest, of course. But there are plenty of people selling diamonds who are happy to stretch the truth to make a sale. Here are six ways you can tell that your diamond retailer isn’t telling you the truth.
1. Their Diamond Grading Reports Aren't From GIA and AGS
This is the biggest problem in the diamond business. Diamond grading reports from the Gemological Institute of America (GIA), is the industry standard that diamond pricing is based on. GIA is a not-for-profit institute that has consumer protection as part of its mission. AGS is also a non-profit and equally respected, although much smaller.
Diamonds with reports from other grading labs, except GIA, aren’t worth as much even if they have the same grade because diamond professionals assume that their grades have been inflated. For-profit laboratories have a financial incentive to please their customers. And their customers aren’t consumers like you: their customers are retailers who want their diamonds to look better than they are. That’s why we don’t recommend buying from retailers who offer these intentionally confusing reports.
2. They Are Selling An "Ideal Cut" Fancy Shape Without an AGS Report
Ideal cut diamonds are round brilliants. Fancy shape diamonds, which are every other diamond shape besides round, don't have the same kind of ideal proportions. The exception is cushion and princess cuts, which, if they are square, can display the hearts and arrows you see in the best round brilliants.
The only fancy shape cut grades that mean anything are from the American Gem Society Laboratories, which use light performance and not any set of “ideal proportions.” AGS only issues them for cushion, emerald, princess and oval cuts. If a fancy shape diamond has a 0 cut grade on an AGS labs report, it’s an ideal cut. If it doesn’t, it isn’t. Some online retailers let you search for “ideal cut” in their fancy shape diamond search and give you a grab bag of what they say are ideal cuts. Does that fancy shape diamond have an AGS report? No? Then it isn’t an ideal cut, period.
3. They Don't Show Diamond Fluorescence in the Listing
Diamond fluorescence is a complicated topic: it’s bad in excess and reduces the value of fine colored diamonds, but it may actually slightly increase the value of off-color diamonds. But one thing that’s not complicated? Sellers who don’t tell you about a diamond’s fluorescence or try to tell you that strong fluorescence doesn’t matter and gloss over the topic. They are probably trying to dump a lemon on you.
4. They Confuse Diamond Center Stone Weight With Diamond Total Weight
If a retailer tries to sell you a “one-carat diamond ring” and it turns out that the one-carat refers to all the diamonds in the ring and not the center stone, that seems a little conveniently confusing, don't you think? It’s OK to give the total weight, of course. But it should be really clear that’s what you are getting. Always make sure you understand what diamond weights are referring to specifically before you make a purchase decision.
5. The GIA Report Number Doesn't Match
Not all retailers show you the GIA report number online. That’s because diamond cutters protect their largest customers by not making it obvious that smaller vendors are selling the same exact diamonds for less. But when you receive your diamond, you can use GIA Report Check to confirm that the report on the GIA website matches the report you received. Many diamonds also have the report number laser inscribed on the girdle. Make sure the number on the diamond matches the number on the report you receive with the diamond.
6. They Claim to be "GIA Certified"
GIA doesn’t certify anything diamonds, gemologists, or retailers. GIA offers diamond grading reports. It doesn't certify diamonds or offers a guarantee. GIA offers a Graduate Gemologist degree, it doesn’t certify gemologists. If you say you are a GIA certified gemologist you are not telling the truth.
Here are a few signs that tell you a retailer is trustworthy that go beyond customer testimonials. They are Jewelers Vigilance Committee members. You can talk to a gemologist, not just a salesperson. They know diamonds, not just reports. They tell you that you’re crazy when you tell them you want to buy a D Flawless instead of just taking your big pile of money. They talk you out of diamonds you say you want to buy. They actually make jewelry. They care about responsible sourcing and can back that up with more than vague talk about “The Kimberley Process.” They try to make you a more educated diamond consumer instead of trying to confuse you.