Not every diamond has a waist size, diamonds with GIA certificates usually have a waist size, but diamonds without GIA certificates will not have a waist size. There are many places where diamonds are mined, and basically large diamond mining sources have authoritative appraisal institutions such as GIA and IGI. However, not all mined diamonds will be sent to appraisal institutions for certification. Considering quality, cost, and other issues, some diamonds will not be certified and will not have waist size.
The reason why diamonds do not have waist sizes
1. Cost increase
GIA diamonds with laser coding at the waist are charged separately, and the larger the diamond, the higher the fee. In order to save some expenses, some diamond dealers do not require engraving on the diamond.
2. Maintain the integrity of diamonds
Although diamond waist size does not affect the grade of the diamond and the marks are not obvious, overall it will leave some artificial marks on the diamond. Some people in Europe and America do not like to leave marks on pure diamonds, so some of the diamonds sold do not have laser coding.