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Support Services: Grading Labs

Support Services: Grading Labs

Grading laboratories play one of the most important supporting roles in our industry. They provide the system upon which consumers have grown to understand diamonds, and a basis for diamond industry professionals to trade. Before the establishment of the 4 Cs, jewelers used vague terms without any recognized standards to communicate a diamond’s value. It was a system open to wide interpretation. The establishment of grading standards gave consumers a measure of security and confidence, and helped diamonds to become the eternal symbol of love and value that they are today. Grading laboratories have also been at the forefront of research and development in the industry, and continue to play this pivotal role.

Of the 4 Cs, cut, clarity, color, and carat size, only a diamond’s size has long been standardized. A carat comes from the weight of the carob seed. This seed is harvested from the carob tree, which is native to the Mediterranean, and has been in cultivation for more than 4,000 years. Although the carob seed itself is inedible, it was found to have a remarkably consistent size and weight, and was used for centuries by gem and pearl traders in counterbalance scales to measure the weight of gems. In 1907, the Fourth General Conference on Weights and Measures adopted the metric carat as the official measurement for gemstone weights, which is universally accepted today as measuring 0.2 grams.

However, prior to the 1940s, there was no standard way to measure a diamond’s cut, clarity, or color. Terms such as ‘tinted’ or ‘tinctured’ could be used to describe color, ‘without flaws’ or ‘with imperfections’ to describe clarity, and ‘made well’ or ‘made poorly’ to describe cut. This obviously made it very difficult for jewelers and consumers alike to assign a recognizable value to their goods.

Some early attempts at defining a color scale were made, but they were not universally accepted. There was a scale using A, B, and C, another using Roman numerals I, II, III, or numbers 0,1,2,3. These systems lacked both the range to address the many different colors of diamonds, and the consistency of application to be understood by consumers. In the early 1930s, former retail jeweler Robert Shipley aimed to change things forever by professionalizing the American jewelry industry. He established the Gemological Institute of America (GIA), as well as the American Gem Society (AGS), whose members were graduates of the GIA. He defined the 4 Cs, and this system began to achieve acceptance after being adopted by both De Beers and the Jewelers Circular-Keystone magazine (JCK). The reason why today’s diamond color scheme goes from D to Z is that Shipley wanted to create a new system, one that wouldn’t be confused with any of the previous systems, thereby relegating A, B, and C colors to the pages of history.

The first GIA grading certificates did not surface until 1955. The grading system in use at that time was very similar to the one in use today. In the early 1970s, GIA introduced some small changes, including the differentiation of flawless and internally flawless to replace what had previously been a single classification, as well as the addition of the I3 clarity grade, and the change of the name from ‘imperfect’ to ‘included’.

Although GIA terminology is the recognized standard in most of the world, especially in the US, other systems have been developed by different organizations around the world. Organizations such as Confédération Internationale de la Bijouterie, Joaillerie, Orfèvrerie (CIBJO), America Gem Society (AGS), International Diamond Counsel (IGC), and European Gemological Laboratory (EGL), have each developed their own system for grading diamonds. However, the differences in each system are in their master sets that define each color and clarity step. Today, almost all grading laboratories use a similar classification system.

However, this does not mean that all labs are created equal. The past 15 years have been tumultuous times for the global grading industry. Even today, diamonds graded from certain laboratories will be traded at a discounted price compared to diamonds with the same grading from another lab, on the basis that the grading standards are more lax at certain facilities. Two independent studies from 2013-2014 both showed inconsistencies in grading, even from different locations within the same organization. Studies by both IDEX and Rapaport concluded that grading is subject to a range of interpretation because of a lack of accepted and binding standards. In 2014, Rapaport took the bold step of refusing to allow diamonds with EGL International certificates to be listed on its trading platform.

The playing field in the grading industry today is quite broad, with a number of for-profit and non-profit companies offering grading, training, gemology and diamond specific courses, and related research and development. The big players include GIA, AGS, GSI (Gemological Science International), HRD Antwerp, EGL USA, IGI (International Gemological Institute, and more recently, De Beers IIDGR (International Institute of Diamond Grading and Research).

Although grading laboratories are best known in the industry and amongst the public for the grading certificates they issue, many don’t realize that these organizations are often at the forefront of research and development in the industry. GIA, for example, was established as a non-profit business whose revenues are reinvested into diamond research, as well as into research on other gemstones. As technologies and diamond treatments have developed over the years, it has been the grading laboratories that have developed the tools to stay on top of the latest changes. Their work has helped the industry to distinguish between many different types of treatments, including irradiation of yellow diamonds in the 1950s, glass-filled rubies and fracture-filled diamonds in the 1980s, and the detection of moissanite and HPHT treatments in the 1990s.

More recently, grading labs have focused heavily on R&D into the rapidly growing synthetic diamond industry, in an effort to both understand the changing technologies being used by synthetic producers, as well as to develop tools and equipment used in their detection. This has led to the development of GIA’s DiamondCheck machine for the detection of synthetic diamonds. More recently, GIA announced two new projects: the use of Radio-Frequency Identification (RFID) to quickly scan and identify individual diamonds in a large batch, and a set of tools to track a diamond from the mine to manufacturing and wholesale.

Diamond grading labs are essential to our industry, as is the need for them to remain consistent, impartial, and free from corruption. The development of the 4 Cs at around the same time as diamonds were becoming a mainstream consumer product was essential in building acceptance of and confidence in our product. With the rapid development of synthetic diamonds and other diamonds simulants and treatments, the grading labs must continue to play a key governance role for our entire industry.

  The views expressed here are solely those of the author in his private capacity. No one should act upon any opinion or information in this website without consulting a professional qualified adviser.

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