Three academics (Amr Al-Azm, Salam al-Kuntar, and Brian I. Daniels) who have been training Syrian preservationists in Southern Turkey have some more anecdotal insights into how deep the connection between ISIS and the illicit antiquities trade is in an OpEd appearing in the International NY Times:
In extensive conversations with those working and living in areas currently under ISIS control, we learned that ISIS is indeed involved in the illicit antiquities trade, but in a way that is more complex and insidious than we expected. (Our contacts and sources, whom we cannot name for reasons of their safety, continue their work under the most dangerous of conditions.)
ISIS does not seem to have devoted the manpower of its army to the active work of looting archaeological sites. Rather, its involvement is financial. In general, ISIS permits local inhabitants to dig at these sites in exchange for a percentage of the monetary value of any finds.
The group’s rationale for this levy is the Islamic khums tax, according to which Muslims are required to pay a percentage of the value of any goods or treasure recovered from the ground. ISIS claims to be the legitimate recipient of such proceeds.
The amount levied for the khums varies by region and the type of object recovered. In ISIS-controlled areas at the periphery of Aleppo Province in Syria, the khums is 20 percent. In the Raqqa region, the levy can reach up to 50 percent or even higher if the finds are from the Islamic period (beginning in the early-to-mid-seventh century) or made of precious metals like gold.
The scale of looting varies considerably under this system, and much is left to the discretion of local ISIS leaders. For a few areas, such as the ancient sites along Euphrates, ISIS leaders have encouraged digging by semiprofessional field crews. These teams are often from Iraq and are applying and profiting from their experience looting ancient sites there. They operate with a “license” from ISIS, and an ISIS representative is assigned to oversee their work to ensure the proper use of heavy machinery and to verify accurate payment of the khums.
But how much exactly does this amount to? The answer is difficult to quantify. As Sam Hardy points out, the recent claim that ISIS has garnered $36m from antiquities looted in its territory is likely inaccurate:
I can only reiterate that it is (literally) unimaginable that the Islamic State is making $36m from a 0.2%-0.4% share of the market value of the antiquities that have been looted from one district under its rule (as $36m from a 20% khums tax on looters’ and traffickers’ own 1%-2% share would imply a trade value of $9b-$18b of antiquities from al-Nabk alone).