Most Expensive Hermès Birkin Bags in the World: The Exotic Skins, Diamond Hardware and More Luxe Details. Hannah Malach. Fri, December 27, 2024 at 4:08 PM UTC. 4 min read.

The title of "most expensive diamond in the world" depends on the criteria used. By market value, the Cullinan Diamond (all stones combined) leads with an estimated $400 million.

However, her previous engagement rings, per Town & Country, include a rare pink diamond from Ben Affleck in 2002 valued at over $2.5M and an 8.5-carat green diamond ring, valued at $5M in 2022.