This is a typical question that I get asked a lot from people who are shopping for fancy cut stones – “What is the difference between radiant and cushion cut diamonds?”. For the layman, it is understandable for people to get confused between a cushion cut and a radiant cut since they look very much alike.
These 2 diamond cutting styles display similar sized table facets and may sometimes even possess similar outlines. Yet, you can make the distinction by looking at the corners of the stone. Cushion diamonds can be identified with curved corners whereas radiant cuts have straight 45° slanted corners.
If you are in doubt, you can always cross reference the lab grading report of the stone in question. Look under the section of shape and cutting style to get your answers. Typically, cushion cuts are listed as a term that’s labeled with cushion brilliant or cushion modified brilliant. On the other hand, radiant cut diamonds are usually identified as Cut-Cornered Rectangular Modified Brilliant.
A Typical Description for Cushion Brilliants From GIA
Note: Radiant cut is a definition set by the diamond jewelry trade. GIA labels these diamonds differently.
As you can see, it is pretty obvious and understandable once you locate the corresponding information from the report. Lastly, I do need to mention that there are some other forms and styles in which cushion cut diamonds are exist. For example, modern branded cuts like the hearts and arrows Brellia and the vintage Old Miner’s cut can be listed as different cutting styles even though they belong to the same family of cushion cuts.
In summary, the general outline of cushions consists of rounded corners. The tell-tale sign of radiant cuts are straight slanted corners. If you simply bear this in mind when looking at diamonds, you shouldn’t have major problems in the correct identification.