"The Insane Story Of How A $430,000 Diamond Went Missing Forever At The Monaco GP"

GQ article from 2019 about a 2004 race:

As part of a sponsorship deal with the aforementioned Ocean's Eleven sequel, the movie's promoters and the team made the absolutely baffling joint decision to run the two Jaguar F1 cars that race (piloted by Mark Webber and Christian Klien at the time) with a literal diamond set into the front nose of each car. That's not one, but two diamonds.

We're not making this up. It was an actual decision that was actually made. On a track perhaps best known for claiming the front end of Formula 1 cars than any other. They weren't even put in specially for the race — Christian Klien was tearing around Monte Carlo, $300,000 diamond strapped to his front wing and all, on Thursday practice with barely anyone watching.

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In what was ultimately a measure of Webber's cool skill behind the wheel of an F1 car, the diamond on his Jaguar went throughout the race unscathed. The diamond on Klien's car unfortunately lasted all of one lap.