The year was 1739 and the army of Nadir Quli Khan, the self-proclaimed Shah of Persia, stood at the outskirts of Delhi. In the city waited Mohammed Shah, the Mogul Emperor of India. It was not the Mogul's city the Persian wanted. He had come for the Mogul's treasure: the Peacock Throne, the Timur Ruby, and the diamonds from the Golconda mines - diamonds with names like the Great Mogul, the Moon of the Mountains, the Sea of Light, and another which had served as a talisman to Carna, the legendary hero of India. The jewels carried power, wealth, and - it was said - the life force of their previous owners. Throughout history men have search- ed for jewels. They have killed for them, died for them, given them names, and like Nadir Shah, contributed to their legends. It is a diamond's history, not its perfection, that makes it most valuable. As Nadir Shah settled down to the sacking of Delhi, he gave little thought to the earlier owners of the jewels he now gathered; nor was he troubled by the souls of the 30,000 men, women, and children he had ordered his army to slaughter that day. Nevertheless, Nadir Shah was unhappy. Something was still missing. He had before him the Peacock Throne, the Moon of the Mountains, the Sea of Light, and thousands of other jewels, but the diamond of legend, Carna's stone, was missing from the Mogul's treasure. For two months the men of Nadir Shah searched for the missing diamond. At last a woman of the Mogul's harem volunteered the secret. The diamond was wrapped in the Mogul's turban. A public dinner was arranged to reinstate the Mogul. As a gesture of good will, Nadir Shah proposed an exchange of turbans. By custom the Mogul could not refuse. Nadir Shah withdrew to his tent. It is said that when the stone rolled free from the yards of cloth which had hidden it, he cried "Koh-i-noor," which means "Mountain of Light." And thus the diamond was named. Nadir Shah returned to Persia, taking the treasure with him. But from that day misfortune traveled with him and with his successors. Soon the diamonds began to vanish: first, the Moon of the Mountains was stolen; next, the Great Mogul disappeared. Battles no longer went his way, and much of the land he had won, he now lost. Less than two years later, Nadir Shah was dead. His son, Shah Rukh, was forced to retreat to the holy city of Meshed. There he sat for hours, it was said, gazing at the Koh-i-noor. And there his ambitious neighbor, Mir Allum, came disguised as a pilgrim to depose Shah Rukh and demand the diamond. Shah Rukh handed over the city, but refused to give up the Koh-i-noor. His eyes were put out, but still he said no. Boiling pitch was poured on his head. News of Mir Allum's treachery reached Ahmed Shah, the Afghan ruler. He rode into Meshed, killed Mir Allum, and kept the Koh-i-noor for himself. Ahmed Shah's grandson Shuja blinded his brother and usurped his brother's throne to gain possession of the stone. But for him, as for so many others before him, the diamond brought neither power nor wealth. Shah Shuja was forced into exile; Ranjit Singh, the Lion of Punjab, accepted the stone in exchange for sanctuary. The diamond remained in Punjab until 1849. After the Sikh Mutiny, it was confiscated by the British and presented to Queen Victoria. She felt the stone lacked brilliance and put it away in a box. The Koh-i-noor is now on display with the Crown Jewels in the Tower of London. As for the rest of the treasure that Nadir Shah brought back to Persia, it proved as elusive to the last Shah as it had been to the first. The Shah of Iran left it behind when he fled Teheran in 1979. Nadir Shah was not the first to come to India in search of jewels and to carry away bad luck. In 1668, Jean Baptiste Tavernier, a Parisian gem expert, acquired a large blue diamond which had been pried from the forehead of a statue of the Hindu goddess Rama Sita. Tavernier returned to France taking with him Sita's curse and the notorious Hope diamond. He sold the jewel to Louis XIV, who named it the Blue Diamond of the Crown, wore it, and shortly died of smallpox. Tavernier, himself, was killed by a pack of wild dogs as he once again traveled East. Louis XV stayed away from the stone and survived to a respectable age. But Louis XVI and Marie Antoinette, both of whom were fond of the Blue, suffered the guillotine. They had already lost the diamond. Stolen dur- ing the Revolution, it went to Holland where it was recut. The diamond cutter, Wilhelm Fals, is reported to have died of grief when his son, Hendrick, stole the diamond from him. The unhappy Hendrick killed himself. The diamond was bought in 1830 by a London banker, Henry Philip Hope, and for 60 years the stone was at peace. But in 1890 the trouble resumed. The Duke of Newcastle, who inherited the Hope, first lost his wife, then lost his fortune. The diamond was sold to a European prince who presented it to a dancer he loved, and then shot her dead in a jealous rage. The gem dealer who next handled the Hope drove off a cliff along with his family, but not before he sold the diamond to the Turkish Sultan Abdul Hamid II. The Sultan was deposed the following year. In 1911 the Hope diamond was purchased by Evalyn Walsh McLean, the wife of the owner of The Washington Post. She became the diamond's most devoted owner. Her son was killed in a car accident, her husband died in a mental institution, her daughter died of an overdose of sleeping pills; but throughout her misfortunes, Mrs. McLean refused to believe that the Hope was unlucky. Following Mrs. McLean's death, Harry Winston, the New York jeweler, purchased the infamous diamond and in 1958 presented it to the Smithsonian Institution in Washington, D.C., where, despite Sita's curse, the Hope has brought pleasure to millions who view it each year. (ELIZABETH LINKER is a free-lance writer and novelist based in North Richland Hills, Texas.)