Graff's Lesedi La Rona revealed as a 302.37-carat square emerald cut

Graff revealed the polished diamond resulting from the 1,109-carat rough stone called Lesedi La Rona. The 302.37 carat square emerald cut diamond produced by Graff's craftsmen is the largest, highest color and highest clarity diamond ever graded by GIA and the world’s largest known square emerald cut diamond.

The company reported that its master polishers needed 18 months of meticulous craftsmanship to "mark this historic moment in diamond history."

On its website, the company reported that "using highly sophisticated software, custom built to tackle the magnitude of the Lesedi La Rona, Graff’s gemologists looked deep within the diamond, plotting the natural imperfections inside the stone with complete precision. At first, the analysis of the stone concluded that a 300-carat principal diamond simply wasn’t achievable. Laurence Graff, however, was convinced that it could be possible, and he set the challenge to the team of expert gemmologists and highly skilled polishers."

"The initial incisions to the stone were made with state-of-the-art lasers. Graff’s master craftsman, an expert in this field and a classically trained musician, used his highly attuned musician’s ear to listen for the smooth progression of the laser."

View the entire probes here: https://www.graff.com/famous-diamonds/lesedi-la-rona/