Round Brilliant Cut Diamond Engagement Rings

Another reason that round brilliant cut diamonds are so commonly used, is that they are available in sizes from 1 mm upwards. Other diamond shapes such as emerald cut diamonds, princess cut diamonds, radiant cut diamonds and cushion cut diamonds are not available in such small sizes, so this makes the round brilliant cut diamond a great choice, particularly for the small diamond content in an engagement ring.

The round brilliant cut diamond is so precisely cut these days, that it is possible for diamond grading laboratories to give it a cut grade, from “poor” through to “excellent”. Fancy cut types such cushion, emerald, oval and princess cut diamonds (to name but a few), are not given a cut grade, as their cut varies so much from diamond to diamond. The first round cut diamonds were very basic and in fact were not really very round at all. That was due to the method of cutting and the equipment available at the time to polish the diamond surface. As technology improved, so too did the cut of the round diamond. This meant that we moved from a round and lumpy cut called the “mine cut”, to the “antique brilliant” cut (among others). These were often only fairly round and tended to have quite varied cut parameters.

Over the years gem cutters realized that some diamonds looked better that others. With analysis of these better cut diamonds, it was possible to make some comparisons and find common features in the cut that would produce a brighter more brilliant diamond which is why it was given the name “brilliant cut”. Once diamond cutting moved from artistry to science, the cut parameters could be measured and calculated for optimum light refraction. Basically if you have a prism made from pure crystalized carbon, (diamond in other words), it should be possible to perfect the cut and shape of the facets to disperse white light entering the diamond and direct the colours of the spectrum to the eye.

These days Certifying labs like the GIA ( Gemological Institute of America ) spend much of their research time in perfecting the cut parameters, and for the round brilliant cut they have developed the “Excellent” cut grade. Long before the GIA, around 100 years ago, a mathematician called Marcel Tolkoski calculated what he believed to be the perfect round brilliant cut parameters based on the angles of light refraction. Specific values were given to table width, pavilion angle crown height, girdle thickness and facet size. He came up with the fact that 57 facets in total seemed to give the best result and balance.

Diamonds cut with fewer and larger facets show big flashes of light, but less frequently than a diamond that is cut with a greater number of smaller facets. These diamonds have a more “glittery” effect, which is not seen as desirable. When Marcel came up with the optimum number of facets at 57 in total, the “Tolkoski Brilliant” was born. The GIA have and other notable labs like AGS ( American gemological Society ) have fine tuned some of these cut parameters, increasing the table width tolerance to between 53 – 62 % of the diamond’s total diameter. It has been said that the most recent advancements in diamond cutting technology has improved the Tolkoski brilliant by around 5-6 %, so Marcel was not too far off the mark, especially considering the tools and technology that are available to us today to measure and perfect these aspects of diamond cutting.

Even with all the technology available to us, most diamonds do not reach an “excellent” cut grade. Clearly an “excellent” cut grade is not so easy to achieve, as otherwise every round brilliant cut diamond ever cut would be an excellent cut.

If you want your engagement ring to sparkle, having the best cut diamond possible produces the best display of light refraction. Choosing a great diamond is all about achieving a balance in the quality elements, and the round brilliant cut really will benefit from being a better cut than it would from having a clarity that is higher than VS1. As with all diamond selection, sound advice is critical. Please do not hesitate to contact us at Ellissi if you have any questions or would like to make an appointment for a diamond engagement ring consultation.