|
|
 |
 Certificate |
|
|
|
| |
| |
 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, colour, and carat), measurements, and
physical properties, define each stone: |
| |
| |
 Its weight. |
| |
Its clarity. |
| |
Its colour and fluorescence. |
| |
Its proportions. |
| |
Its finish. |
| |
Its measurements: diameter,
height or thickness, minimum and maximum diameter with the girdle. |
| |
Any defect of the stone structure
must be noted on the certificate, example: possible trace of laser drilling or « rough » trace. |
|
|
| |
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 of diamonds
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 colour grade or clarity grade of
a diamond. |
| |
|
| |
Be careful with these terms:
« clarity enhanced » and « colour enhanced » which are reproduced
sometimes on the certificates. It means that you are in the presence of a
diamond whose clarity (or colour) 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 and rigorous are: |
| |
| |
GIA (Gemological Institute of
America)
- Offices: United States, Italy, Hong Kong, Japan, Korea, Thailand, Taiwan, United Kingdom, Russia, China.
- Website: GIA |
| |
|
| |
HRD (Hoge Raad voor Diamant)
- Office: Belgium.
- Website: HRD |
| |
|
| |
IGI (International Gemmological Institute)
- Offices: Belgium, United States, India, Thailand, Japan.
- Website: IGI |
| |
|
| |
AGS (American Gem Society)
- Office: United States.
- Website: AGS |
| |
|
| |
LFG (Laboratoire Français
de Gemmologie) Service Public du Contrôle des diamants, perles fines et pierres précieuses in
the Chambre de Commerce et d'Industrie of Paris.
- Office: France.
- Website: LFG |
| |
|
| |
Gubelin Gem Lab
- Office: Switzerland.
- Website: Gubelin Gem Lab |
|
|
|
| |
| |
| Example of certificates |
|
 |
 |
 |
 |
| GIA |
HRD |
IGI |
AGS |
|
| Fancy colour certificates |
 |
 |
| GIA Fancy Colour |
Gubelin Gem Lab Fancy Colour |
|
|
|
|
 |
1.32 carat F-VS1 |
|
0.29 carat H-SI1 |
|
0.89 carat H-VVS2 |
|
1.36 carat F-VS1 |
|
1.39 carat G-IF |
|
| Price: £ 7,198 |
|
| Price: £ 261 |
|
| Price: £ 3,369 |
|
| Price: £ 7,416 |
|
| Price: £ 8,229 |
|
|
|
|
