GIA, IGI, HRD, AGS and EGL Diamond Certificate, Diamond Certification
- Date of Appearance
- Its Characteristics
- Gemological Laboratories
- GIA (Gemological Institute of America)
- HRD (Hoge Raad voor Diamant)
- IGI (International Gemological Institute)
- AGS Laboratories
- EGL USA
- EGL (European Gemological laboratory)
Date of Appearance
Certificates appeared in 1970, they radically changed the ways and customs of the profession.
Its Characteristics
The certificate is a diamond grading report, describing objective factors, both qualitative and quantitative, and an almost infinite combination of all of the variables, based on the 4 c's (cut, clarity, color, and carat), measurements, and physical properties, define each stone.
It appears under a plasticized printed paper on which are noted the characteristics of the diamond which was evaluated. Holograms, particular textures, micro-texts were incorporated into the certificate to secure it.
Laboratories of gemology offer various types of certificates who are declined in several sizes: full certificate, small certificate, credit card format, etc...
You can find on a gemological certificate the following informations:
- Shape and Cutting style.
- Carat Weight.
- Clarity grade.
- Color grade.
- Fluorescence grade.
- Cut Grade (or Proportions), only for round-brillant cut diamond.
- Polish.
- Symmetry.
- Measurements: diameter, width or depth, mini and maxi diameter in millimeters.
- Girdle, Culet, Table%, etc...
- Date.
- Any defect of the stone structure must be noted on the certificate, example: possible trace of laser drilling or « rough » trace.
Laboratories of gemology have sometimes their specificities, some of them will indicate the proportions of the diamond on the certificate (the HRD for example), the others will prefer to indicate the cut grade (the GIA or the IGI for examples).
Online Verification Service: today all the laboratories of gemology offer to check online that the information on your report matches what is archived in their database.
- GIA: GIA Check Report (service available for Diamond Grading Reports issued after January 1, 2000)
- HRD: HRD Antwerp Certificate Link
- IGI: IGI Online Data Retrieval (service available for Diamond Grading Reports issued after June 1, 2004)
- AGS: AGS Check Grading Report
- EGL USA: EGL USA Check Grading Report (service available for Diamond Grading Reports issued after 1995)
They offer also optional services such as the laser inscription of the certificate number or the possibility of sealing the diamond in a plastic box, etc...
Upon request, the diamond can be sealed in a plastic holder together with a microfilm of the certificate.
Not only does the sealing keep the diamond safe from damage, grease and dirt, it is also a guarantee that a given certificate and the accompanying stone actually belong together.
Laser inscription is a process of using a very fine, precise laser beam to write a customized personal message (« I love you », « Marry me », etc...) or certificate number on the girdle. The laser inscription is microscopic, totally invisible to the naked eye.
It can only be seen with a jewelers' 10x magnifying loupe and it does not change the color grade or clarity grade of a diamond.
Be careful with these terms: « clarity enhanced » and « color enhanced » which are noted sometimes on the certificates. It means that you are in the presence of a diamond whose clarity (or color) was modified, in order to improve it. This term is noted on the certificate in the section « Comments ». It is sold at a discounted price.
Gemological Laboratories
The main gemological laboratories in the world, and most known are:
GIA (Gemological Institute of America)
Global Presences: United States, Belgium, Israel, India, South Africa, Botswana, Thailand, Hong Kong, Japan.
Comments: it is one of the best laboratories of gemology in the world. It is recognized by our profession as being an excellent laboratory. It is reliable and impartial.
Website: GIA
Examples of GIA Certificates:
GIA Diamond Grading Report
GIA Diamond Dossier
GIA Fancy Color
HRD (Hoge Raad voor Diamant)
Global Presence: Belgium (Antwerp), India, Turkey.
Comments: it is one of the best laboratories of gemology in the world. It is recognized by our profession as being an excellent laboratory. It is reliable and impartial.
Website: HRD
Examples of HRD Certificates:
HRD Diamond Certificate
HRD Diamond Identification Report
HRD Fancy Color
IGI (International Gemological Institute)
Global Presence: Belgium (Antwerp), Italy, Israel, United States, India, Thailand, Hong Kong, China, Japan.
Comments: it is a good laboratory of gemology. It is recognized by our profession as being a good laboratory.
Website: IGI
Examples of IGI Certificates:
IGI Diamond Certificate
IGI Diamond Identification Report
IGI Fancy Color
Global Presence: United States.
Comments: it is a very good laboratory of gemology. It is recognized by our profession as being a very good laboratory. It is reliable and impartial.
Website: AGS
Examples of AGS Certificates:
AGS Diamond Quality® Document
AGS Diamond Quality® Report
AGS Platinum Diamond Quality® Document
Global Presence: United States, Canada.
Comments: the reliability of appraisal of this laboratory is disputed among the diamond professionals. We advise you to degrade of 1 degree the color and/or the clarity which is noted on their report. In 1986, this laboratory became independent and it is thus more affiliated with the other laboratories EGL (Belgium, Israel, South Africa, Hong-Kong, etc...). This laboratory provide also identification for rough diamonds.
Website: EGL USA
Examples of EGL USA Certificates:
EGL USA
EGL USA Analysis
EGL USA Fancy Color
EGL (European Gemological laboratory)
Global Presence: Belgium, Israel, South Africa, Hong-Kong, United Kingdom, Korea.
Comments: the reliability of appraisal of this laboratory is disputed among the diamond professionals. We advise you to degrade of 1 or 2 degree the color and/or the clarity which is noted on their report.
Website: EGL
Examples of EGL Certificates:
EGL
EGL International
EGL Fancy Color
