"The International Gemological Institute (IGI) recently analyzed and graded a polished lab-grown diamond over 50 carats—the largest on record—as well as another novelty, a multicolored lab-grown"

https://www.jckonline.com/editorial-article/igi-largest-multi-colored-lab-grown/

Expected lab growth diamonds to be a lot bigger. The Cullinan is over 3000ct