They went to Alexandria on business, stole Saint Mark's body, and then hid it in a shipment of pork, which the Muslims didn't check very carefully because, you know, they were disgusted by it. You can actually see a version of this on the mosaics in the Basilica of Saint Mark, complete with the Muslims shouting an Arabic version of, like, eww, gross. And then forever after, the Venetians were like, listen, we have to trade with these guys. We use it as a secret way to ferry saint bodies out of Egypt. We don't want to become fantastically wealthy. It's just a necessary byproduct of our saint savings. So what did Venice import?