The Power of Light
Diamonds are renowned for their ability to transmit light and sparkle so intensely. We often think of a diamond's cut as shape (round, emerald, pear), but a diamond's cut grade is really about how well a diamond's facets interact with light.
A diamond's cut is crucial to the stone's final beauty and value. And of all the diamond 4Cs, it is the most complex and technically difficult to analyze.
The cut grade is determined by how successfully a diamond interacts with light. Three of the visual effects that are created are:
Brightness: Internal and external white light reflected from a diamond
Fire: The scattering of white light into all the colors of the rainbow
Scintillation: The amount of sparkle a diamond produces, and the pattern of light and dark areas caused by reflections within the diamond
Here are images of what happens to light (blue line) when it hits a diamond with three different qualities of cut:
When you're researching diamonds, you'll hear the terms "Table", "Depth", and "Width" quite a lot... to understand where on the diamond those terms are coming from, check out this chart: