The Graff Pink

Private collector Laurence Graff purchased the $46.2 million worth of The Graff Pink, priced at $1.85 million per carat, from its famous creator, American jeweller Harry Winston, in 2010. This stunning ring, one of the most expensive pieces of jewellery in the world has a pink diamond of 24.78 carats, a rare type II colour diamond with the finest rating, designated as one of the greatest diamonds found. The pink has a perfect rectangular step cut, with delicately rounded corners, and is set between two shield-shaped diamonds. The three diamonds are mounted on a platinum ring.
source by https://www.wonderslist.com/10-most-expensive-jewellery-pieces-in-the-world/