Nadir Shah’s Throne In Topkapi Palace Museum – Chapter 2,
Nadir Shah chose to send the famous Keykavus Throne which he had brought back from Delhi and entrusting it to Mehmed Mandi Han and Sanli Mustafa Han the throne was sent to the Ottoman Sultan Mahmud the First along with many other gifts. The caravan carrying the boxes filled with gifts set out for Istanbul. For Nadir Shah, Sultan Mahmud the First had a dagger ornamented with huge emeralds and rubies made. Besides this, he had several loads of treasures made ready and sent them to Iran. The envoys of Nadir Shah and the Sultan set off and met near Baghdad on May 30, 1747. With a special ceremony they showed each other the gifts they were carrying and a few days later they went their separate ways. Just as the Ottoman delegation reached the city of Hemedan, there was a large uprising in Iran. Nadir Shah was captured and put to death as he tried to escape from the headquarters in Fethabad. There was only one thing that the Ottoman delegation could do, that was to turn around and go back to Istanbul taking their gifts with them. After great difficulties, they reached the Ottoman border without any of the treasures being plundered and delivered all the gifts to the Ottoman treasury. The Iran envoy learned of the uprising and Nadir Shah’s death while In Baghdad. Mehmed Mehdi Han was Nadir Han’s most trusted official and for him to return to Iran meant certain death. So he chose to seek asylum from the Ottomans. This request was accepted in a note sent to Baghdad in which it also ordered that the gifts be carefully guarded. A short while later another order came asking that Nadir Shah’s gifts be sent to Istanbul. Thus the Keyktvus Throne Throne was taken to Istanbul along with many other valuables.
You can find more details about Nadir Shah’s Throne In Topkapi Palace Museum in Istanbul in Chapter 3.