Giving Compass' Take:

• Research from RAND Corporation begins to reveal the extent of the Islamic State's archaeological looting in Syria.

• What further research is needed to understand the scope of this problem? How can funders help to restore significant cultural artifacts to the Syrian people? 

• Learn about the role of charities and terrorism in Syria

The Islamic State surrendered its last scrap of territory, in Baghouz, Syria, this past March.

While some argue that celebrations of IS's demise are premature, there's no question that the terrorist group left a trail of destruction in its wake.

Many lives were lost, of course. But a looming issue is the group's legacy of looting.

During IS's seemingly unstoppable rise, looted artifacts were said to be a significant source of income for the group. Value estimates ranged from a few million to several billion dollars.

One of the issues in media reports about the looting is that no one had a firm grasp of just how much was at stake. The dollar figures amounted to guesswork.

We still don't know exactly what's missing. But no one had identified the value, using empirical data and systematic calculations, of the artifacts that were known to exist in these archaeological sites. Until now.

With two Near Eastern archaeologists and two art market researchers on our team, we recently published a paper in the International Journal of Cultural Property that offers the first attempt to quantify the market value of artifacts at the level of a site.

The excavated objects' total value was larger than we had expected. We found that just a small portion of a site can yield thousands of objects, adding up to millions of dollars.

Based on our model, the total estimated value of all artifacts, not including coins, excavated from Dura Europos to date is US$18 million. At Tell Bi'a, the estimate is $4 million. This range is partly explained by the different sizes of the two cities and the area that was excavated. It's also explained by market interest: Greek and Roman artifacts, which comprise the large majority of objects found at Dura Europos, fetch higher prices at auction than Bronze Age items, which make up the majority of artifacts at Tell Bi'a.

It's important to keep in mind that these dollar figures represent just slices of two sites. The most comprehensive database of Syrian archaeological sites, assembled by archaeologist Jesse Casana and collaborators at Dartmouth College, has identified roughly 15,000 major sites in the country. Data examined by Casana's team suggest that 3,000 of those sites experienced some looting from the start of the Syrian Civil War in April 2011 to mid-2015.

Not every site has the artifactual density or richness of Dura Europos. But if a small portion of a single site like Tell Bi'a is capable of generating $4 million in sales—and there are 15,000 major sites—it doesn't take much imagination to see just how much of an archaeological gold mine the country is.

Read the full article about the Islamic State's archaeological looting in Syria by Fiona Greenland, Oya Topçuoğlu, Tasha Vorderstrasse, James V. Marrone at RAND Corporation.