Radiant Cut Inventor Speaks to Alumni Association Members
By Mauricio Minotta

Henry Grossbard, inventor of the Radiant Cut, and his son, Stanley, gave an educational presentation at GIA recently that covered the history and the essential characteristics behind the well-known diamond cut.

Speaking before members of the Alumni Association’s San Diego Chapter at the Institute’s World Headquarters in Carlsbad, the Grossbards’ seminar, titled “Understanding Radiant Cuts,” included detailed information on evaluating quality and cut in a Radiant and a side-by-side comparison with the Princess Cut.

Rectangular Radiant Cut stones have a “circular life” or facet arrangement, much like a round brilliant, while the square Princess Cut features an alternating black and white facet style that exhibits a very geometric, contrasting appearance.

Grossbard described his cut as having a softer, more elegant look because of the faceted corners and a smaller table, which is designed to accentuate its larger crown and bring out more brilliance. The proportions on the Princess Cut differ in that its square shape features sharp corners with a flat crown, larger table and a deep pavilion.

“The Radiant Cut is essentially a hybrid of the brilliant and the step cut,” Stanley Grossbard said during the Sept. 23 lecture. “Proportionally, it can range from a full rectangle to a perfect square.”

He also noted that unlike the step cut, which is best appreciated with a high clarity grade stone, the Radiant Cut’s round-brilliant-style faceting is very effective in hiding inclusions through the crown. Diamonds with clarity grades as low as SI2 can be used for the cut with no visible sign of their inclusions with the unaided eye, Grossbard said.

The cut’s hybrid nature allows light to enter the diamond from many angles – allowing light to reflect in numerous ways within the diamond, they said. Depending on the pavilion angle, a Radiant Cut stone can either have a “crushed ice” look, which has vibrant sparkle, but less distinct facets, or a traditional appearance that highlights the brilliant facets.

Encouraged by Alumni member Meir Opalek to organize a presentation, the Grossbards’ seminar was the third in a series that started in Delaware Valley, Pennsylvania, where they spoke to 65 members of the Alumni chapter. They were also invited to speak to the Golden Gate Chapter in San Francisco before lecturing in Carlsbad.

Henry Grossbard developed the cut in 1976 and introduced it to the market the following year. The emerald cut was extremely unpopular at the time because it lacked life and was hard to sell, Stanley Grossbard said.

“Since my dad liked the shape so much, he wanted to make the emerald cut popular again, so he created the brilliance that people wanted for the emerald cut stone,” he said.

The design was patented in 1977, which the Grossbards held for 17 years. They won a four-year litigation against an Israeli manufacturer that was illegally copying the Radiant Cut, but the high court costs and the time-consuming effort to preserve their patent proved to be too intrusive when the Grossbards faced the possibility of a second litigation.

“We stepped back and allowed other people to start cutting the Radiant Cut. The Radiant Cut quickly became a fully accepted member of the family of diamond shapes, cut by many manufacturers throughout the world,” Stanley Grossbard said.

“But by continuing to cut only the finest proportioned Radiant Cuts, we have retained a niche true to my father’s vision.”