Mesopotamian sculptures, jewellery and stelae sold legally have commanded stunning sums, up to 1 million US dollars in some cases, but the Syrian and Iraqi looters would be selling them to foreign dealers for a fraction of that cost and their "profit margin coming from the sheer number of artifacts being sold".
"The looted artifacts most likely follow the traditional smuggling routes for all sorts of illicit goods into Turkey, according to Lynda Albertson, head of the Association for Research into Crimes Against Art. From there, the most common route is through Bulgaria and the Balkans into Western Europe. Britain and the United States remain the biggest markets for antiquities, though wealthy collectors are emerging in China and the Gulf—especially for Islamic-era artifacts. International bans make the ultimate sale of illicit antiquities difficult, but not impossible. So far, there have been no reports of major, museum-quality pieces from ISIS-held territory appearing in auction houses, so the artifacts must be going to either private collectors or they are being hoarded by dealers to be slowly and discretely released onto the market, said Patty Gerstenblith, Director of the Center for Art, Museum and Cultural Heritage Law at DePaul University. “I do believe that dealers are willing to warehouse items for a long time and that they may be receiving some ‘financing’ to do this from well-heeled collectors or other dealers operating outside of the Middle East,” she said. “It is relatively unlikely that a major piece would be plausibly sold on the open market with a story that it was in a private collection for a long period of time.”'Iraq says ISIS demolishes ruins to cover up looting operations', Asharq Al-Awsat, 12 May, 2015.