The lunchbox, stolen last week, was recovered along with a ruby and gold teacup, saucer and teaspoon.
Two men from the southern city of Hyderabad have been arrested.
The items, valued at $7m (£5.4m), once belonged to Mir Osman Ali Khan, the last Nizam (king) of Hyderabad and once the richest man in the world.
Police allege the two men had fled to the western city of Mumbai in the hopes of finding a buyer for the stolen goods where they lived a "fancy life" in a five-star hotel for a few days.
