The International Gemological Institute (IGI)

Established in 1975, the IGI is the largest gemological organization of its kind, with 18 laboratories and eight schools of gemology around the world. The IGI serves more consumer buyers than any other gemological institution, issuing grading reports for finished jewelry, in addition to loose natural, lab grown diamond and colored gemstone certification. The IGI was the first laboratory to grade “Hearts and Arrows” diamonds and pioneered full grading of lab grown diamonds in 2005, gaining more experience in that area than any other gemological institution.

PriceScope Pointer: The IGI grades finished jewelry, as well as loose gemstones, and established itself as a world leader in lab grown diamond certification in 2005.

IGI Natural Diamond Report

The IGI natural diamond report provides a 4Cs assessment with a plotted clarity diagram. The IGI only provides a cut-grade for round brilliant diamonds. All other shapes are only graded for polish and symmetry, not for cut.

IGI Laboratory Grown Diamond Report

The gold standard for lab grown diamonds, the IGI Lab Grown Diamond report provides 4Cs assessment, a clarity plot, and standardized diamond photo. It is offered with or without Hearts and Arrows assessment.

IGI Hearts and Arrows Diamond Report

The IGI Hearts and Arrows report is associated with Excellent-Ideal cuts of superior quality. The report provides 4Cs assessment, with diamond-specific micrographs showing Hearts and Arrows quality.

IGI Colored Stone Report

The IGI colored stone report reflects state of the art analysis. IGI screens every gemstone using the most advanced technologies to determine naturally mined, laboratory grown or simulant origin. Experienced graduate gemologists conduct further assessment in controlled conditions, detailing relevant gemological characteristics according to the strictest international system.

IGI Jewelry Report

The IGI Jewelry Report provides all gemstone and mounting specifics, as well as clear standardized photos showing details of craftsmanship that may not otherwise be visible. More complex than the analysis of loose gemstones, IGI’s expertise in the analysis and documentation of finished jewelry items is unrivaled.

IGI Jewelry Report: Small Format

The small format IGI Jewelry Report provides reliable details and specifics for mounted jewelry at a cost that is more practical for the subject pieces. More complex than the analysis of loose gemstones, IGI’s expertise in the analysis and documentation of finished jewelry items is unrivaled.

The Gem Certification and Assurance Lab (GCAL)

Established in 2001, the GCAL is the only laboratory issuing diamond “certificates” backed by a guarantee. The GCAL focuses on diamond cut analysis, using a copyrighted diamond-specific performance assessment method, and provides a unique diamond fingerprint known as Gemprint. The GCAL offers sophisticated imaging, is one of two top-tier laboratories offering cut grading for certain fancy shapes and is the world’s only only ISO 17025 Accredited Forensic Gem Laboratory.

PriceScope Pointer: The GCAL is best known for high quality photo and video services, lab grown diamond grading, Gemprint, and issuing a true diamond “certification.”

GCAL Guaranteed Diamond Grading Certificate

The GCAL Diamond Certificate has a 4Cs assessment, Gemprint diagram and Photomicrographs. It also comes with a diamond-specific Light Performance Profile indicating optical brilliance, optical symmetry and Hearts and Arrows (optional), which you can read about in our section on Cut Quality.

GCAL Guaranteed Lab-Grown Diamond Certificate

The GCAL Lab-Grown Diamond Certificate has the features of the Diamond Grading Certificate but is framed in a different color and indicates lab grown origin and growth-method.

GCAL Supplemental information online: Video and Photos

For an additional fee, the GCAL offers additional services. These include Gemprint, a non-invasive, positive identification technology for each diamond which has been used by the FBI and Canadian Government, along with independent, standardized diamond photography and videography.

egl

European Gemological Laboratories (EGL)

For many years overseas EGL locations over-graded diamonds. Over grading occurs when a laboratory consistently issues better color or clarity grades for diamonds than they would normally according to strict, industry-accepted international standards. The practice became egregious enough that in September, 2014, all EGL-graded diamonds were delisted and removed from the world’s largest trading platform.

“The Rapaport Group is opposed to the misrepresentation of diamond quality. The over grading of diamonds is an unfair practice that destroys consumer confidence and the legitimacy of the diamond industry… The diamond trade must prioritize the protection of consumers above profits.”

EGL-graded Diamonds Removed from PriceScope

Soon after The Rapaport Group came to this conclusion, PriceScope also made the decision to remove all EGL-graded diamonds from our search engine in the interest of consumer protection.

PriceScope Pointer: Buyer beware – Certain EGL locations are infamous for famously over grading diamonds, in some cases by 3-4 grades, allowing unscrupulous sellers to overcharge consumers.

Our Advice

In any situation where an EGL graded diamond is being considered for purchase, we recommend the buyer hire his or her own gemological expert to analyze and accurately grade the diamond according to strict, industry-accepted international standards.

Jewelry Reports

When shopping in malls and department stores you will see “certificates” for finished jewelry. These documents should not be confused with loose diamond grading reports. They are commissioned by the store and issued by a winning bidder, often assembly-line style for thousands of articles at a time. They lack the precision and strictness of loose diamond grading reports which report on a single, specific gemstone.

Variable Standards

Grades for diamonds in finished jewelry can be inflated. Most jewelry grading is done for big box stores that solicit bids from competing graders. ‘Discount laboratories,’ which primarily exist to write jewelry reports, inflate color and clarity grades to win and keep big contracts. The situation is so common that many shoppers in malls get a false, negative first impression regarding warmer colors and normally eye-clean clarity grades.

Jewelry sellers using eCommerce platforms like eBay may use discount laboratories for jewelry grading, since inflated grades make their products seem more competitively priced in searches.

Some top-tier laboratories do issue jewelry reports. These institutes, known for loose diamond and gemstone grading, are more capable of enforcing strict, internationally accepted standards than little-known discount laboratories which would not exist without the chain stores they serve.

PRACTICAL ANALOGY: Combo Meal versus À La Carte

For daily-wear pieces at economical prices a finished jewelry report is useful, as long as the grading context above is understood. Like a combo-meal, it inexpensively provides information about a jewelry piece’s gemstones, metal content, etc. in a simple, affordable manner. Alternately, a diamond costing hundreds or thousands of dollars by itself should be treated à la carte, accompanied by its own report from a top-tier laboratory, describing the diamond only.

Get full protection: Our vetted vendors Whiteflash, Blue Nile and James Allen sell diamonds graded by top-tier laboratories. As an added layer of protection, those vendors have in-house gemologists inspect those diamonds to ensure accurate grading.

Advanced Diamond Certification

With any subjective measure there are bound to be differences. Honest differences of opinion are understandable. Intentional differences are another matter.

What is Standard Deviation?

When grading color and clarity reputable gemologists use a set of strict, industry-accepted international standards established by the GIA in the 1950s. Top-tier laboratories and appraisers use calibrated master color stone-sets and uniform clarity standards to ensure a baseline of uniformity lab to lab and location to location.

With that said, no two diamonds are alike. Color and clarity occur on a sliding scale and a diamond sitting directly on the border of two grades may come out on one side of the other, depending on the subjective opinion of the gemologist making the judgment.

To that end, a standard deviation of +/- one grade is generally deemed acceptable among professionals. While this is logical from an analytic standpoint a difference of even one grade may have a significant influence on value. For this reason it’s important for a buyer and a seller to agree on the document of authority prior to sale.

Vendor Policies

The influence of standard deviation on diamond grading and value is mitigated when you buy from a seller who offers a full credit upgrade policy. Under such a policy the full amount you pay remains available for you to apply again to a different diamond, apples to apples, for the duration of that policy.

Long term benefits: Few sellers anywhere match the policies of Whiteflash, offering you 100% upgrade credit toward a new diamond that costs more than your original spend. Blue Nile and James Allen offer full credit toward a new diamond costing 2X or more than your original spend. The money you invest with these PriceScope vendors can ultimately be used again, toward your next significant purchase.

What is Over Grading?

Over grading occurs when a laboratory, appraiser or seller continually promotes diamonds as having better color or clarity grades than they would normally receive according to strict, industry-accepted international standards.

For example, a person stating that a diamond has “F color, VS2 clarity” where top-tier laboratories or appraisers would collectively judge it to have H color, SI1 clarity – is over grading that diamond.

Why Over Grade?

Imagine that Simple Sam is shopping for a diamond. “Honest Abe Jewelers” only sells diamonds graded by top-tier laboratories. Simple Sam is considering these two diamonds from Honest Abe. He really wants the F color, but it’s stretching his budget.

• 1.00 carat F – VS2 Ideal cut for $9,000
• 1.00 carat H – VS2 Ideal cut for $7,000

“Terrible Herb Jewelers” says he can make Sam a better deal:

• 1.00 carat F – VS2 Ideal cut for $8,000*

Sam believes this is a no-brainer and buys the 1.00 carat diamond from Terrible Herb. Unfortunately, nobody told him about over grading so he didn’t end up with a diamond graded by a top-tier lab.

What happened? 

*Sam paid $8,000 for a diamond that would have been graded H – SI1 by a top-tier lab. So, not only did he fail to achieve his color goal… he paid $1,000 more for a diamond with lower color and clarity than Honest Abe was offering him for $7,000. Terrible Herb was even rewarded by Sam’s lack of education, paying his diamond supplier far less for that misrepresented, over-graded diamond than Abe would have paid his supplier for correctly graded diamonds.

It’s highly possible that down the road, a family member will inherit the diamond and have it appraised only to find out Sam was gouged by an unscrupulous seller.