Most grading reports give round brilliant diamonds an overall cut grade, but fancy shapes such as ovals, pears, emeralds and cushions usually receive only polish and symmetry grades, so you need to judge their cut from proportions, outline and how they look. That makes it worth knowing what to check before you choose a fancy shape.
Here is why fancy shapes are graded differently and how to assess them.
Why fancy shapes lack a single cut grade
A round brilliant has one well studied ideal. Fancy shapes vary much more in outline and facet pattern, and two well cut ovals can look quite different and both be beautiful. Labs therefore report the measurements, polish and symmetry, and leave the overall judgement to the buyer and their jeweller.
Illustration of an oval brilliant, not a specific stone we supply.
What the report does tell you
- Polish. How smooth the facet surfaces are.
- Symmetry. How evenly the facets are shaped and aligned.
- Measurements. Length, width and depth, from which you can work out the length to width ratio.
- Depth and table percentages. Proportions that affect how the stone handles light.
- Girdle and culet. The thickness of the edge and whether there is a small facet at the base.
To read these sections with confidence, see our guide on how to read a GIA diamond certificate.
What to check yourself
- Length to width ratio. This sets the outline. An oval around 1.3 to 1.5 looks classic, while a pear between about 1.4 and 1.7 looks elegant. Preference matters more than rules.
- Bow tie. Many ovals, pears and marquise diamonds show a darker bow tie shape across the centre. A faint one is normal, a heavy one can dull the stone.
- Outline. Look for even shoulders, rounded curves and no flat or bulging sides.
- Spread. A stone that is too deep carries weight that does not show face up, so it looks smaller for its carat weight.
- Light return. Videos and images under consistent lighting show how lively the stone is across its face.
Shape by shape notes
- Oval and pear. Watch the bow tie and the shape of the shoulders.
- Emerald and Asscher. Step cuts show clarity more, so check the step pattern is even and clean.
- Cushion. Some show chunky facets, others a finer crushed ice look. Choose the look you prefer.
- Radiant and princess. Check the corners for chips and that the sparkle is even across the face.
How we help
When we source a fancy shape, we review the report, the proportions and the images or video of each candidate before recommending it, and we explain what we see. Choosing between two or three stones side by side is often the clearest way to decide.
Designing yours with us
Every piece is designed with you in CAD first, and you can have as many revisions as you need, within reason. Once you are happy, a 70% deposit starts the making. Your piece is crafted by specialist goldsmiths, UK hallmarked and sent by insured tracked courier. Diamonds come with a GIA or IGI report. Bespoke rings start from £600.
Browse our lab grown diamonds, design your bespoke engagement ring, or read about the bespoke journey to see how a commission works from first chat to delivery.
Frequently asked questions
Do oval diamonds have a cut grade?
Most reports do not give ovals or other fancy shapes an overall cut grade, only polish and symmetry.
How do I judge the cut of a fancy shape diamond?
Look at the length to width ratio, outline, bow tie, depth and how the stone looks in images or video.
What is a bow tie in a diamond?
A darker bow tie shaped area across the centre of some elongated diamonds. A faint one is normal.
Are polish and symmetry enough to judge a fancy shape?
They help, but proportions and how the stone looks matter just as much.