GIA does grade lab diamonds, but these diamonds usually come at a premium. IGI is still preferred for lab as it is cheaper and the quality tbh is on par or sometimes even stricter than GIA for lab diamonds (). Also, it’s easier to compare IGI lab diamonds as most lab diamonds are IGI graded. I recommend just going for IGI graded diamond and save the money.
The quote is from Ada diamonds. You should read the rest of Ada's reddit posts too and their website.
Ada does alot of filtering of their lab grown diamonds into their inventory, as most lab grown diamonds are poorly grown.
https://www.adadiamonds.com/good-vs-bad-lab-diamonds
- Low quality lab diamonds are cheaper to produce and get sold to unsuspecting members of the public via budget e-commerce web sites.
- Just because two lab diamonds received the same 4Cs grading does not mean they will look the same.
- High Pressure High Temperature (HPHT) diamonds with excess boron can have a blue tinge and phosphorescence. Irradiated HPHT diamonds with excess titanium and aluminum can look gray. Chemical Vapor Deposition (CVD) diamonds that were grown too quickly can look brown. CVD diamonds with iterative growth patterns can appear lifeless and cloudy. CVD diamonds can also have black surface inclusions from excess polycrystalline. CVD diamonds grown on cheap seeds can have blurriness from crystal strain and graining.
- These elements are not obvious at first glance to a non lab diamond expert. These characteristics also reduce resale value.
- Beautiful lab diamonds take patience. The faster you grow a diamond, regardless of method, the worse the quality. Growing colorless, high clarity diamonds is much more time consuming and expensive than growing dark, heavily included diamonds. While diamond growth technology has improved, many growers who are capable of producing nice diamonds actively choose to grow ugly ones because it is so much cheaper to do so.
- Some growers take short-cuts like HPHT treatment, irradiation, and bad cutting methods to produce as many lab diamonds as possible. But those ugly diamonds are not worthy of an Ada Diamonds client.
- There are a number of nascent diamond growers around the globe contributing to an abundant supply of bad lab diamonds. These diamonds are grown quickly and cheaply and then sold on budget ecommerce sites to unsuspecting members of the public.
Ada diamonds already cherry picks the IGI lab growns, to weed out those that have inflated gradings. Plus this is based on a sample size of only 17 diamonds. It's hard to use this as an accurate date, when the sample size is very small, and the 17 diamonds are already filtered to be the better ones by themselves. What they are trying to say is in Adas diamonds, their IGI certified stones that are picked out by Ada, have consistent grades.
They recommend IGI certs to save cost. But if you see their prices, they are selling the diamonds very high.
A 1.2ct+ D-E, IF-VVS2, costs SGD 8,300 - 10,300 (with taxes). That's like double the market price... and for a normal 57 facets round.
Comparing the price for an IGI certified diamond, and them recommending IGI because its cheaper doesn't really make sense. lol
Also, the sample size only mentions about Color and Clarity. There are other gradings like the Cut, Polish and Symmetry, Fluorescence, etc. to consider.
IGI Cut parameter is also known to be the worse amongst the labs.
IGI was one of the first lab to jump into certifying lab growns. GIA, AGS, GCAL only followed later after doing more research to standardize their grading.
The quality of lab grown diamonds has changed over the years, but are still very mixed. There are off undertone hues issue of gray, brown, blue, striation issues, birefringence, etc. (which Ada says they filter out).
These issues are all mixed into the mass majority of growers in China, which is also IGI. A singular retailer like Ada diamond, would work with 1 lab in 1 country. But this does not apply to all IGI certs around the world, where there are different IGI labs with different standards.
This guy submitted the same stone to different IGI labs and got different gradings -
https://www.diamonds.pro/education/igi/
So essentially, diamond companies would choose the IGI labs that give the best grading. lol
I'm assuming the test was probably done for naturals and not lab growns. Though I still think it's very weird that a lab would have a different set of standards for naturals vs lab growns. It's not ethically right IMO.
That being said, GIA does have different labs in different countries too. But they are reputable because the different labs have consistent standards.
AGS only has 1 lab in the US. So quality control would be easier for them.
Another good read about certificate comparison,
https://www.moltenore.co/post/compa...aboratories-the-ultimate-diamond-buying-guideSimilar to EGL, personally I would not purchase diamonds with [IGI] certificate too. Or if I have to, I would be more cautious. There are also times where IGI has reported to give 2-3 grades better than GIA/AGS.
However, we have also heard of some companies who choose to send their stones to IGI instead to attain a better grade on paper. Many consumers have paid much more for an IGI graded diamond thinking they actually had good deal. Do remember that most diamond prices are based on GIA's standards. So if you convert it to GIA's grading, how much would your diamond now be worth?
I would just say, buy at your own risk. Many customers who seek regrading at GIA or AGS have reported receiving discrepancies in their certificates.
It's not easy for a buyer to filter out poor undertones, striation, etc. for lab grown diamonds. It can only be seen under certain types of lightings. If you buy an IGI diamond off the bat, you are in big danger with all these things. Not to mention the extremely loose cut grade, which is why Ada needs to cherry pick the best out of the lot. And Ada warns against public e-commerce sites as these are where all these problematic diamond gets sold to unsuspecting consumers. Though they do charge a high premium for filtering those out. But them charging that amount for IGI cert and saying that IGI certs saves more money.. doesn't make sense.
I checked the cost to certify a diamond with GIA.
https://www.gia.edu/doc/Lab_FeeSchedule_LabGrown_EN_USD_2022_0701.pdfFor a lab grown 1ct, it's USD 125. It's really not expensive. I don't know how much cheaper IGI charges, but even if it costs 50% less, that's only about a USD 62 price difference.
I don't think the savings for USD 62 is worth it to risk everything else.
IGI is also know for their inflated valuations too. Though not all diamonds from IGI might necessarily be bad, the likelihood of picking a consistent grading from them is low. It requires alot of filtering not just in the basic grades, but physical inspection too (just like what Ada diamonds said).
Btw, IGI was recently sold to a China giant company, Fosun. Fosun China owns several jewellery brands in China. The purpose of getting a certification in the first place is to get a 3rd party unbiasedness in the grading. Now you have a China company that owns the lab, selling diamonds that they certify themselves. That leaves alot of pondering..