The incident, which was captured on CCTV, took place at around 6.30 am in Gujari area near Ambabai Temple, they said.
The trader, Kantilal Jasawantraj Mehta, arrived here at around 5.30 am from Mumbai by a private bus to deliver the ornaments as per an order, they said.
He came to Gujari by an auto-rickshaw and was going to a temple when four persons attacked him with a sword and sticks. They snatched the bag containing the ornaments valued at more than Rs 35 lakh and escaped in a car, police said.