Amy asks Jonathan from Jonathan’s Fine Jewelers…
I am researching cushion cut stones and was wondering what in your opinion was the best range was for crown angle, depth percentage, and crown height. I like the look of a rectangular cushion.
The Perfect Cushion Cut Diamond – The Short Answer
Amy, thanks for your question! The short answer is that there is to pick what you like! I personally like a cushion to be 60-65% depth and 58-62% table. Everyone wants a formula to help them make a decision when they really need to let their eyes be the judge.
What proportions should you look for when buying a Cushion cut?
This simple question is the most difficult question to answer in the diamond industry today. The modern cushion cut has been around for maybe 5 or 6 years and is a remake of the old mine cut which is over 100 years old. The popularity of the cushion cut is due to the popularity of settings such as the halo, as well as the fact that the cushion cut can come the closest of any fancy shape to resembling the brilliance of a round diamond.
Another reason this is difficult to answer is that there is no cut grade on a GIA certificate of a non-round cut diamond, and it is impossible to cut a non-round diamond to ideal proportions by round standards. This is because the crown and pavilion angles vary as you go around the perimeter of the diamond (i.e. the distance from the girdle to the culet changes as you circle around the diamond).
Categories of Cushion Cut Diamonds
There are two basic categories of cushion cut diamonds, the modified cushion brilliant and the much rarer cushion brilliant cut. The difference is in the faceting of the pavilion of the diamond. The cushion brilliant cut is a rarer cut because it is less retentive of the raw diamond crystal (i.e. more raw material must be whittled away to achieve this cut). Since the cushion brilliant cut is more wasteful of the raw material, the resultant polished diamond is more expensive. I prefer the brilliance of a cushion brilliant cut to a modified cushion brilliant cut, but they are not always prettier, they are difficult to locate, and I could argue that while I prefer the cushion brilliant cut, I do not necessarily think they are worth the extra money.
Within the category of modified cushion brilliant there are rectangular and square cushion cuts. This is a matter of preference, and this choice would generally be made based on the style of ring that the consumer would select. After a consumer picks a basic “outline” that appeals to them (square or elongated) they are faced with choosing between a spreadier (bigger looking) cushion that has the appearance of “crushed ice ” when you look at it which is to say that it has little pin fire sparkles throughout, or a cushion cut that is less big looking and more resembles the appearance of a round diamond in that it has a more solid light reflection but less busyness or twinkle. This too is a matter of preference. I personally prefer the latter.
When I sit down with an overseas cutter, I might have to look at 100 cushion cut diamonds to buy one. I reject a higher percentage of cushion cuts than any other shape because so many are just not that pretty. I am looking for a pretty outline or shape, followed by a brilliant diamond with the least amount of light leakage, followed by good square footage (length and width measurements) for the weight…this is tricky because I want bigger looking but not at the expense of brilliance.
I reject diamonds that have been graded liberally by the lab such as SI1′s and SI2′s with big black spots or prominent center imperfections. While I personally do not generally take issue with florescence, I make sure that a diamond with florescence is priced favorably relative to its peers. Finally, if the diamond meets all of my criteria, I will still pass on it if it is not a good value relative to other diamonds available on the market. For people looking for tips on what to look for in buying a cushion cut diamond, let me just say that buying a cushion cut is like buying any other diamond. It boils down to picking the diamond that speaks loudest to you personally.
