A diamond quality chart for laboratory-grown diamonds typically follows the same criteria as those used for natural diamonds, encompassing the four Cs: Cut, Colour, Clarity, and Carat weight. Here’s a detailed breakdown:
- Cut: This refers to how well a diamond’s facets interact with light. Precision in the cut of a diamond greatly influences its brilliance, fire, and overall appearance. Cuts are typically graded from Excellent to Poor.
- Colour: Colour grading for lab-grown diamonds measures the degree to which a diamond is colourless. Diamond colour grades descend from D (colourless) to Z (light colour). For lab-grown diamonds, the focus is usually on the higher end of the scale, where the stones are mostly colourless or near colourless.
- Clarity: Clarity refers to the absence of inclusions and blemishes. Even though lab-grown diamonds can be engineered to have fewer imperfections, they are still graded on a scale from Flawless (FL) to Included (I), which reflects the visibility of these characteristics under 10x magnification.
- Carat Weight: Carat weight is the measurement of how much a diamond weighs, with one carat being equivalent to 200 milligrams. The carat weight alone doesn’t dictate the diamond's value, as the other three Cs also play significant roles.
In addition to these traditional factors, laboratory-grown diamonds may also be evaluated based on the technology used to create them (HPHT vs. CVD), which can influence the presence of certain types of inclusions or colour hues.
This quality chart can be a useful tool when comparing laboratory-grown diamonds, allowing consumers to make informed decisions based on standardised grading metrics.