Because diamonds are considered as investments, several organizations exist to grade and certify these commodities. These companies spread world-wide function independently but follow the international norms and standards in grading and certifying diamonds.

Each certification process has an industry standard and this is provided by the GIA, the Gemological Institute of America The international parameters set by the GIA is the minimum standard criteria worldwide There is also the American Gemological Society which grades the color of diamonds and gemstones during diamond certification. The criteria they employ for rating hue are deemed better than that of the GIA.

There are also the Accurate Gemological Labs. AGL and the EGL (European Gemological Laboratories) is its European counterpart. AGL's primary function is to furnish a comprehensive report on the diamond after a careful evaluation of its 4 C's. The EGL follows the norms laid down by the AGL and even besides that gives its own report about the various proportions of the diamond. This includes the pavilion and crown angles, which makes his report all the more complete

International Gemological Institute (GMI) IGI It also has a diamond certification process which is similar to that of the diamond certification process of the Europeans. In addition, they address the diamond gem's angle and crown aspects. The main benefit is that these are less expensive than the GIA. Small and medium-sized diamonds are the most sought after ones.

Any talk of diamonds has to include Australian, which is also true of diamond certifying. They have the Independent Gemological Laboratory, or the IGL, which is valued as being very accurate and specific in their work. Every single one of the diamonds presented to be certified is subjected to a high-precision examination for purity, color, and other attributes; the diamond is then re-evaluated by another certifier, and the results are compared.

We have Hoge Raad voor Diamant or, more commonly referred to as "Diamond High Council", too. It is a Belgian company that is known the world over with the certification of diamonds of high quality Their certification is in accordance with standard high quality international guidelines. It's company policy never to reveal the name of the owner of the diamond, which it may be the evaluator to eliminate the risk of bias in their reports There is also the Gubelin Labs, located in Switzerland, founded by the highly recognized Dr. Edward Gubelin (the namesake). They are also a highly recognized company, in the diamond certification field, which appraises gemstones.