The mother-of-two - who was announced as the face of Tiffany & Co back in 2017 - completed the look with a white singlet and black pointed-toe heels.
Supermodel Kendall Jenner was the VIP guest at the event.
According to The Daily Telegraph, the Victoria's Secret Model earned an eye-watering $500,000 for her brief appearance, with the publication estimating Kendall's hourly fee to be a whopping $21,000.
WATCH: Kendall Jenner Flaunts Stunning Look at Sydney's Tiffany & Co Event