Diamond Grading: Diamond Certificates (Certs)
Gemological Laboratory Certification
Why do you need a laboratory certification for your diamond? Although it may seem like a needless expense, a diamond certificates, grading report, certificate of authenticity, appraisal report, or "cert" may be your only assurance that you are getting exactly what you paid for. Diamonds are tested for the basics (cut dimensions and proportions, clarity, color, and carat weight) and they are also tested for traces of gem enhancement, and wether they are synthetic.
Although even a lay-person may be able to tell the difference between a triple-zero diamond and a cheap, poorly cut SI-3 grade stone, there is very little (visible) difference between a FL stone and a IF or VVS-1 stone - other than the price, which can be substantially different. If you are purchasing an "investment grade" diamond it is essential to have a detailed cert from a reputable gemological laboratory that specializes in diamonds - not only for resale, but for insurance appraisal as well.
GIA Certificate
A GIA (Gemological Institute of America) report provides detailed information about the dimensions, carat weight, shape and cut of a stone. GIA reports also cover any treatments or enhancements that have been done, and of corse, wether the stone is natural or synthetic. Although GIA's diamond grading methodology is the industry standard they are also known for their "colored stone grading system" used to quantify the hue, tone, and saturation of a colored stone.
The GIA was founded by Robert M. Shipley in 1931, the same year that Shipley published his groundbreaking book titled 'Gemology.' GIA's world headquarters are located in Carlsbad, California, with offices around the globe.
IGI Certificate
The International Gemological Institute (IGI) is the oldest institute of its kind in Antwerp, founded in 1975, and is the largest independent gem certification and appraisal institute in the United States, with operations in New York City, Los Angeles, Toronto, Antwerp, Bangkok, Mumbai, Tokyo, Dubai and Hong Kong. The IGI offers Identification Reports, Appraisal Reports, Certificates of Authenticity, and Attestations of Origin.
The IGI lab grades diamonds as well as colored gemstones along several basic criteria which include: shape and cut, clarity, origin (colored gems), mesurments, weight, color, and finish.
HRD Antwerp Diamond Certificate
The certificates department of HRD Antwerp in Antwerpen, Belgium issues quality reports for loose (unmounted) polished diamonds according to ISO 17025 international standards for gemelogical testing laboratories. All diamonds are examined anonymously, and the graders can not know the identity of the owner. HRD also offers gemelogical training and continuing education courses in diamond grading, the sorting of rough diamonds, jewellery design and gemology.
HRD uses the "Hearts and Arrows" measuring system which was developed by HRD Antwerp scientists, as well as quantifying the standard parameters of Clarity, Cut, Carat Weight, Shape, Color, and Fluorescence. HRD's refined Cut Grading system measures each of the three parameters (proportions, polish and symmetry) using a scale ranging from Excellent to Fair, with "Triple Excellent" being the highest overall designation.
As well as testing for synthetic diamonds, the HRD lab also uses state-of-the-art technology to test for subtle and hard to recognize enhancements such as HPHT. To insure the security of their documents, HRD uses complex watermarking to prevent copying or falsifying their reports, and gives you the option of having your diamond returned in a tamper-proof sealed container to insure that a given certificate and the accompanying diamond belong together. Aditionally, certificates issued after January 1, 2005 can be viewed online.
AGSL Certificate
The AGSL was the first gem lab to grade a diamond's cut quality using three parameters: Polish, Symmetry, and Proportions. Each parameter is given a 'grade' from 0 (Ideal) to 10 (Poor). In 2004 AGS added a new category referred to as "Light Performance" but to retained the "Triple Zero" monicker for diamonds with a perfect score, 'Polish' and 'Symmetry' were merged into one category called "Finish," and "Proportions" was renamed "Proportion Factors." The AGS Cut Grading system was developed through of years of research by gemologists, mathematicians, and optical physicists.
Full Article: AGSL Diamond Quality Report
Further Information on Diamond Grading
GIA, GIA Diamond Color Grading  . www.gia.edu
IGI, Diamond & Jewelry Certification . www.igi-usa.com
HRD, HRD Diamond Color Grading . www.hrd.be
Sarin, Sarin Gem Labs - Diamond Grading . www.sarin.com
AGS, AGS Consumer Website . www.americangemsociety.org
Insured Shipping of Loose Diamonds & Jewelry
Brink's Global Services, Shipping Diamonds & Jewelry . www.brinksglobal.com
Brink's, Incorporated, Shipping in the U.S. . www.us.brinksinc.com
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