The model was spotted without the jewelry while walking the red carpet but was pictured with the noticeable piece later in the night.
The divorced couple is starring together on 2023 Dancing With the Stars tour.
The couple began dating in 2013 and got engaged in April 2021.
The couple is also parents to two daughters- Maxima Chan Zuckerberg and August Chan Zuckerberg born on November 30, 2015, and August 28, 2017, respectively.
Josh Hartnett stepped away from the spotlight to focus on his mental health.
“Cora is healthy and adorable, and we are proud and grateful.”