De Beers Group will shut down its lab-grown diamond brand Lightbox as part of its “Origins Strategy” to refocus on natural diamonds and improve profitability. The move comes amid falling lab-grown diamond prices due to low-cost production in China and discounting in the U.S. market. De Beers CEO Al Cook said the closure supports the group’s transition to a more streamlined and high-return business model. The company will continue investing in industrial synthetic diamond technologies through its subsidiary Element Six.