Jacob & Co. specializes in awe-inspiring stones, and this 90.59 ct. t.w. fancy intense yellow rhomboid-shape diamond drop most definitely falls into that category. Baselworld marks the second time the gem has been shown—it was unveiled at a swank affair in Monaco. According to Philip Nassimi, managing director of high jewelry for the New York City-based firm, the stone is the largest rhomboid-shape diamond ever graded by the GIA.

The platinum riviere necklace that supports the stone features 62.72 cts. t.w. double brilliant-cut colorless diamonds cut by Gabi Tolkowsky. “It took 13 to 15 years just to collect all the stones, and three months to make the necklace,” Nassimi told JCK during the show. As of day six of the fair, the piece was still for sale.

Necklace in platinum with a 90.59 ct. t.w. fancy intense yellow rhomboid-shape diamond drop with 62.72 cts. tw. round double brilliant-cut colorless diamonds, price on request; Jacob & Co.

JCK