Diamond Carat Weight
Diamond carat is often misunderstood and refers to a diamond's weight, not necessarily its size. When comparing diamond carat sizes, take a diamond's cut into consideration as well: a high-carat diamond with a poor cut grade may look smaller, often cut deeper, than a diamond with smaller carat weight and a better cut. Use our buying tips, diamond carat size chart, and expert tips to help you choose the best diamond carat weight for you.
Buying Tips
- Carat is the most misunderstood of the 4Cs. It actually refers to a diamond's weight, not the diamond’s size.
- Consider cut and carat together; a larger carat diamond with a poor cut grade can appear smaller than a smaller diamond with a higher cut grade.
- To maximise your budget, "Buy Shy," which means selecting a carat weight slightly below the whole and half carat marks. For example, instead of a 2.0-carat diamond, consider buying a 1.9-carat weight. This will save a considerable amount of money and the slight size difference will never be noticed.
Diamond Carat Size Chart
Carat Weight considers two factors:
- A Diamond's Top Diameter
It is important to measure, in millimeters, the distance across the top (diameter) of the diamond as this is how it is viewed when set into a ring. - A Diamond's Cut Grade
A diamond's cut grade should also be considered. When a diamond is well cut (grades Very Good or higher), the light reflected out of the top making it appear larger.
How do these two Carat Weight factors help when purchasing a diamond?
The diamond's diameter and cut grade reveal that smaller carat weight diamonds will appear larger with higher cut grades (Very Good and Ideal). On the flip side, a larger carat weight diamond could appear smaller with lower cut grades (Good, Fair and Poor).
More Expert Tips
- If a large carat weight is important to you, yet you're working within a strict budget, consider a diamond with a good cut, SI1-SI2 clarity, and an I, J, or K colour grade.
- Diamond prices jump at the full- and half-carat weights. Diamonds just below these weights cost significantly less, and, because carat weight is distributed across the entirety of the diamond, small size differences are almost impossible to detect.
- Keep in mind that the smaller the finger, the larger the diamond will appear. A 1.5-carat diamond solitaire looks much larger on a size 4 finger than a size 8.
- Not all settings will fit all diamond carats or shapes. If you have already selected a setting, check the diamond specifications of your ring or ask your Blue Nile Diamond and Jewellery Consultant (800-852-3878) for help. If you need a special jewellery piece created, Blue Nile can accommodate almost any request.
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