Each of our diamonds is certified by one of the following professional independent organisations:
| GIA | Gemological Institute of America http://www.gia.edu/ |
| EGL | European Gemological Laboratory International http://www.eglinternational.org/ |
| EGL USA | European Gemological Laboratory USA http://www.eglusa.com/ |
| AGS | American Gem Society Laboratories http://agslab.com/ |
| HRD | Hoge Raad voor Diamant (Diamond High Council) http://www.hrdantwerp.be |
| IGI | International Gemological Institute http://www.igiworldwide.com |
Here’s where things get a little bit confusing. Whilst all these laboratories do a lovely job of certifying diamonds, they don’t always agree on how diamonds should be graded. They each have their own specific criteria for determining the colour and clarity grades and some laboratories are stricter than others. As the following table shows, a diamond graded as G colour, VS2 clarity by GIA would be graded E colour, VS1 clarity by EGL USA.
| Colour Comparisons | GIA | AGS | HRD | IGI | EGL USA | EGL INT |
| Whitest | D | D | ||||
| Ultra White | E | E | D | |||
| Very White | F | F | E | D | D | |
| White | G | G | F | E | E | D |
| White | H | H | G | F | F | E |
| Very Slight Yellow | I | I | H | G | G | F |
| Slight Yellow | J | J | I | H | H | G |
| Clarity Comparisons | GIA | AGS | HRD | IGI | EGL USA | EGL INT |
| 100% 10 x Loupe Clean | FL/IF | IF | ||||
| 100% 10 x Loupe Clean to the untrained eye | VVS1 | VVS1 | LC/LC+ | IF | IF | |
| 100% 10 x Extremely Clean with Loupe | VVS2 | VVS2 | VVS1 | VVS1 | VVS1 | FL/IF |
| 100% Very Clean with 10 x Loupe | VS1 | VS1 | VVS2 | VVS2 | VVS2 | VVS1 |
| 100% Eye Clean | VS2 | VS2 | VS1 | VS1 | VS1 | VVS2 |
| 90% Eye Clean | SI1 | SI1 | VS2 | VS2 | VS2 | VS1 |
| 50% Eye Clean | SI2 | SI2 | SI1 | SI1 | SI1 | VS2 |
| Not Eye Clean | I1 | I1 | SI2 | SI2 | SI2 | SI1 |
| Not Eye Clean | I2 | I2 | I1 | I1 | I1 | SI2 |
You might be wondering how you can possibly compare diamonds when the certifying laboratories can’t even agree! But don’t worry – this is one reason why we developed our unique DiamondScore.
DiamondScore takes these grading differences into account and gives you one clear mark out of ten for each diamond, so choosing the best quality diamond couldn't be easier.