This diamond, like the Kohinoor, was mined at the Golconda mines in Andhra Pradesh, India. It found its way into the possession of the mughal emperors.
In 1739, Nader Shah of Persia invaded India and sacked Delhi; the plunder he garnered from the Mughal treasury included the Darya-i-noor, in addition to the Kohinoor and the Peacock throne. All of these treasures were carried to Persia by Nader Shah and the Darya-i-noor has remained there ever since.
After Nader Shah's death, the Darya-ye Noor was inherited by his grandson, Shahrokh Mirza. It then passed into the possession of Alam Khan Khozeimeh, and later, of Lotf Ali Khan Zand, a member of Iran's Zand dynasty. Agha Mohammad Khan, founder of Qajar dynasty, defeated the Zands, and thus the Darya-e-noor came into the possession of the Qajars. Fath Ali Shah Qajar had his name inscribed on one facet of the diamond. Later, Nasser-al-Din Shah Qajar often wore it on an armband. He apparently believed that this diamond had been one adorning the crown of Cyrus the Great. When armbands fell from royal fashion, he wore the diamond as a brooch. On occasion, the gem would be left in the care of high personages of the land, as a sign of honor. It was eventually kept hidden in the Golestan Palace treasury museum until Mozzafar-al-Din Shah Qajar's time -- this monarch wore it as a hat decoration while visiting Europe in 1902. Reza Shah, founder of the Pahlavi dynasty, wore the diamond as a decoration on his military hat during his coronation in 1926, and it was used in Mohammad Reza Shah Pahlavi's coronation ceremony in 1967