IGI Diamond Certification

The IGI started out as the blue color workhorse of the diamond business.  They were, and still are, the most popular gem lab for the major jewelry chains in the US and Canada (Kay, Zales, etc.)  They are like a factory. They work fast, and they work cheap.

Lately, though, they have been trying to position themselves as a legitimate contender against the other labs and not just a certificate factory for the major chains.  While they haven’t succeeded so much in America, they have actually gained quite impressive market share in Europe and the Middle East.  I used to travel to sell diamonds in Dubai, and the two major certificates sold in that market are HRD and IGI.

The bottom line with IGI in comparison to GIA is that they are consistently looser in color, and partially looser in clarity.  What I mean by this is that specifically in the “SI3″ range, they generally upgrade to an SI2.  Diamonds used for “SI2″ programs at the major chains would almost never pass a GIA “SI2.”  I know this particularly well, as throughout my professional career, I must have personally selected thousands of diamonds to be sold as IGI SI2s at the major jewelry store chains in the US and UK.   These programs (usually the middle-ground price point offering great value as it’s the cheapest of the eye-clean grades) all have a minimum of SI2 clarity. For these programs, we would always strive to find diamonds that were in that “SI3″ sweet spot — diamonds that would not receive an “SI2″ from GIA, but were too nice to sell as an “I1.”

If you have any questions, please post them in the comments below.  I will usually respond within 24 hours.

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  1. daniel     Reply

    Why aren’t you fans of blu enile?

  2. Justin     Reply

    I’ve been researching around for diamonds. I came across Zamir Diamonds having an IGL (International Gemological Laboratories). The prices are surprisingly low, which is why I’m on here. I’m checking the legitimacy of both. Have you heard of either of these and do you think I should trust them with my business?

    Thank you!

    • Mike     Reply

      Hi Justin,

      I don’t know anything about Zamir, but IGL is not an acceptable certificate. Stick with a legitimate certificate (GIA/AGS only).

  3. Nan     Reply

    Hi Mike:
    I always believe that Costco has best price and good quality. I got this ring with IGI cert paid $6400 plus tax from Costco:
    1.01 carat, I, VS2, excellent cut, very good pol/sym, 62.2% TD…
    Now I see the Blue Nile has so many selections with GIA cert. I may get the similar one with only around $5200 and its GIA cert!

    Is Costco the good place to buy a diamond ring? If not, in your opinion which one is good place to go, Blue Nile, Kay or Zales…?

    Thanks a lot!


    • Mike     Reply

      Costco used to be ok, but they have dropped considerably in value the last year or so. They no longer certify rings (I believe under 1.20cts) and they rely far more on IGI than GIA (where they used to usually have GIA certificates over a carat). While we are not fans of Blue Nile, there are plenty of other options to getting better value. It depends what you are looking for.

      If you want specific advice on finding a diamond, feel free to contact us directly. We generally answer a lot faster and write far more detailed responses. We reserve the comments for general statements that can be helpful to everyone.

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