Welcome back to the Diamonds Hatton Garden blog where we bring you the latest insights from our Hatton Garden jewellers. Known for our beautiful diamond engagement rings, we are often asked by couples about how to choose the size of their diamond and what to consider when looking at different shaped diamonds. In today’s entry, we continue our look into fancy shaped diamonds with the regal cushion cut diamond with our guide to cushion cut sizing and what to look for when choosing your cushion cut diamond engagement ring.
History of the cushion cut diamond
Cushion cut diamond engagement rings are one of the most popular choices for diamond engagement rings. The gorgeous shape, which can be traced back to the 1700s, is deeply feminine and captivating. Distinguished by their square or squarish-rectangular outline with curved sides that are either rounded or have slightly pointed corners, cushion cut diamonds are supremely elegant and classic.
What to look for when buying cushion cut diamond engagement rings?
- Focus on H+ colour grades for a cushion cut diamond. This will ensure the diamond looks clear.
- Cushions tend to trap colour, so IJK diamonds will appear more yellow than round diamonds
- Make sure to the diamond is eye-clean.
- Don’t focus on clarity grades too much. Once a diamond is eye-clean, it doesn’t matter what the grade is.
- Look for cushion cuts with a depth and table under 70%.
- Avoid cushion cuts that are not certified by GIA or AGS.
Cushion Cut Diamond Colour – what to choose?
For white diamonds, cushion cuts are one of the worst shapes at retaining colour. Ironically, for fancy coloured diamonds they are one of the best! As with the radiant cut diamond, cushion cuts are the most popular for fancy coloured diamond cuts – the complete opposite of the round brilliant.
When looking at cushion cut diamonds, budget permitting, we recommend starting with H or better (for white gold/platinum and silver settings) or, for yellow or rose gold settings, it’s possible to go down a colour to J or K.
Choosing a H diamond colour represents a good value option, it is an excellent balance in price compared to colour and, from H colour upwards, the price jumps significantly. Whilst colour H is not completely “colourless” the small tint is barely noticeable, especially if the diamond is set into a rose or yellow gold mount.
Cushion Cut Diamond Clarity – what to choose?
Clarity with modified brilliant shapes can be tricky and a cushion cut is no exception. When looking at cushion cuts it is important to gather whether the diamond in question has a “crushed-ice” or classic, antique cushion. A crushed ice diamond is a type of cushion cut diamond that looks like crushed or broken glass which hides inclusions. If you are choosing this style, then moving down on inclusions is acceptable. Of course, for an antique cut where inclusions show up more we recommend the lowest clarity that is still eye-clean.
Cushion Diamond Cut Parameters
For maximum brilliance, we recommend the below parameters for cushion cut diamonds:
- Depth: Under 70%
- Table: Under 70%
- Polish/Symmetry: Good, Very Good, or Excellent
- Length/Width Ratio: Personal preference.
The length and width ratio refer to the proportionate length and width of the diamond and also is a good determinant of how the diamond will look when it is looked at from a face-up view. It is also a good indicator of how big or small the stone will appear to look.
Polish is a grade noted on the lab certificate. It refers to how fine of a polished has been applied to the facets of the diamond. This generally has a minimal impact on the price and look of the diamond.
Symmetry is also a less important grade on the diamond certificate. It refers to how symmetrical the facets of the diamond have been laid out by the cutter. Both Symmetry and Polish should always have a minimum grade of “Very Good.”
Do Carats in Cushion Cut Rings Make a Difference?
When you begin to examine the carat of a cushion cut diamond, you will also find that there may be significant differences in the price points due to the emphasis of the carat weight. Our cushion cut sizing chart helps you to visual the various sizing options:
| Cushion MM Size |
Cushion Weight (ct) |
Diamond ct weight G (Approx) |
|---|---|---|
| 4.2 mm. | 0.40 | 0.52 |
| 4.9 mm. | 0.50 | 0.65 |
| 5.25 mm. | 0.75 | 1.00 |
| 5.5 mm. | 1.00 | 1.40 |
| 6 mm. | 1.25 | 1.80 |
| 6.5 mm. | 1.50 | 2.10 |
| 7 mm. | 2.00 | 2.80 |
| 7.5 mm. | 2.50 | 3.50 |
| Cushion MM Size |
Cushion Weight (ct) |
Diamond ct weight G (Approx) |
|---|---|---|
| 8 mm. | 3.00 | 4.20 |
| 8.5 mm. | 3.50 | 4.90 |
| 9 mm. | 4.12 | 5.80 |
| 9.5 mm. | 5.09 | 7.20 |
| 10 mm. | 5.62 | 7.90 |
| 11 mm. | 7.44 | 10.50 |
| 12 mm. | 9.52 | 13.40 |
| 13 mm. | 12.66 | 17.80 |
Unsure what size round cushion cut diamond to choose? At Diamonds Hatton Garden our team of family-run jewellers have assisted generations of clients to find their perfect cushion cut diamond engagement ring. Contact our team via harel@diamondshg.co.uk or call +44 7951 060238 for more information and to arrange your appointment.