A 12 century key to the Ka'aba sold for £9.2 million ($18.1 million) late Wednesday, setting a new record for an Islamic work of art at auction. The Abbasid period key, made of iron and measuring 37 cm long, sold at Sotheby's in London for more than 18 times its pre-sale estimate and was bought anonymously. It is the only known example to remain in private hands. The key is engraved with the words: “This is what was made for the Holy House of Allah during the time of our lord the Imam son of Imam Al-Muqtadi Abu Ja'far Al-Mustansir Abu'l-Abbas 573.” It was the highlight of the auctioneer's Islamic sale, which realized £21.5 million, in excess of the pre-sale high estimate of £13.1 million and a new record for an Islamic art auction. “Remarkably, the sale realized more than the Islamic department's annual total in 2007, demonstrating beyond doubt the burgeoning and international demand for Islamic Art,” said Edward Gibbs, head of Sotheby's Islamic Art department. The previous record for a work of Islamic art sold at auction is believed to be a bronze fountainhead in the form of a hind dating from mid-10th century Spain. It sold at Christie's in 1997 for £3.6 million. On Tuesday, Christie's held its own London Islamic sale which fetched £11.8 million, including a leaf from a mid-seventh century copy of the Holy Qur'an sold for £2.5 million versus a pre-sale estimate of £100-150,000. It was a new world auction record for an Islamic manuscript, the company said. In addition to the example sold at Sotheby's this week, there are 58 recorded Ka'aba keys, all of which are held in museums. Most, 54, are in the Topkapi Palace Museum in Istanbul, two are in the Nuhad Es-Said Collection, one is in the Louvre in Paris and one is in the Islamic Art Museum in Cairo. Sotheby's called the Ka'aba “arguably one of the most important symbols of Islam.” According to the auctioneer, the tradition of dedicating the key to each Caliph appears to have originated with the Abbasid caliphs in Baghdad. __