Isha Ambani has been spotted with a rare and expensive Hermès Birkin bag, with some reports describing it as the most expensive Birkin bag ever. The bag is said to be adorned with diamonds, with estimates ranging from over 100 carats to 3,025 diamonds, and may be made of solid gold or crocodile skin. However, there is some uncertainty about the details of the bag, including its exact value and materials.