Once the diamonds have been mined and processed, then the diamonds are delivered to sorting experts who classify and assign a value to them. The industrial quality diamonds which are small, lower quality stones are classified. In this sorting process, these diamonds are grouped, based on their size, shape, quality and color in to thousands of categories. Almost all rough diamonds have some differentiating marks, which make each one unique.
After sorting the next step for rough diamonds are cutting and polishing. Cutting of rough diamonds takes a great skill, with diligent techniques that have been practiced for generations. The activity takes place in South Africa, Belgium, China, India, Israel, Russia and the US, among other countries. A well-cut diamond shines light within itself, from one facet to another, as well as through the top of the diamond, and brings out its spectral brilliance.