Step 5: Checking the Girdle
The girdle is the edge between the top and bottom of the stone that helps protect the stone from chipping. The grader will check the girdle condition after assessing the stones clarity. In doing this they will be checking for thickness, condition and laser markings along the girdle;
Thickness – A girdle that is too thick can make the stone look unattractive and could also affect our estimated weight of the stone. The girdle is there to protect the diamond so it should be thick enough to prevent chipping but not so thick that it is unsightly.
Condition – Diamonds girdles are finished in 3 ways. Bruted – is the natural state of the rough diamond, so it has not been altered during the cutting and polishing process, it appears misted. Polished – when the diamond was polished they chose to polish the girdle as well as making it shiny. Faceted – tiny little flat facets have been put onto the girdle during the cutting process.
Laser Markings – Often Gem Laboratories will laser a tiny logo and certificate number onto the girdle of the diamond. This does not affect its clarity grade in any way. If the graders find a number this means they may be able to track the grading report or certificate, and will then have access to the detailed characteristics of the diamond. It is also possible to have messages lasered onto the girdle, which can be polished off.