with minor occurrence as pyrite. The moisture content of the oil shale is low (2 to 5.5%). The major mineral components of the Jordanian oil shale are calcite, quartz, kaolinite, and apatite, along with small amounts of dolomite, feldspar, pyrite, illite, goethite, and gypsum. It has also a relatively high metal content. The eight most important deposits are located in west-central Jordan within east of the Dead Sea. These deposits are Juref ed Darawish, Sultani, Wadi Maghar, El Lajjun, Attarat Umm Ghudran, Khan ez Zabib, Siwaga, and Wadi Thamad. The best-explored deposits are El Lajjun, Sultani, and Juref ed Darawish, and to some extent Attarat Umm Ghudran. They are all classified as shallow and most are suitable for open-cast mining, albeit some are underlain by phosphate beds. In addition to the west-central deposits, another important deposit may be the Yarmouk deposit occurring near Jordan's northern border, and where the resource was first developed. This deposit would be exploitable by underground mining as it reaches some in thickness. A third oil shale region lies in southern Jordan in the Ma'an district. History Humans have used oil shale as a fuel since prehistoric times, because it generally burns without any processing. Its occurrence was known in Jordan from ancient times, as evidenced by its use as a building and decorative material from the ancient Greek, Roman, Byzantine, Umayyad and Abbasid periods. The modern exploitation of Jordanian oil shale began under Ottoman rule prior to and during World War I, when the German Army produced shale oil from the Yarmouk area. The oil shale was processed to operate the Hejaz Railway. It was mined and processed near the Maqarin station along the Haifa spur of the railroad, which partly follows the Yarmouk River valley. In addition to the shale oil production, oil shale was also utilized as a mix with coal to fuel locomotives. The German Geological Mission studied the El Lajjun deposit in 1968. In 1979, the Natural Resources Authority of Jordan commissioned a study from the German Federal Institute of Natural Resources and Geosciences to evaluate the Juref ed Darawish, Sultani, El Lajjun, and El Hisa deposits and in 1980 from Klöckner-Lurgi to evaluate the pre-feasibility of construction of an oil shale retorting complex using Lurgi-Ruhrgas process and a power plant with 300 MW capacity using Lurgi's Circulating Fluidized Bed (CFB) combustion process. In 1980, the Soviet Technopromexport company conducted a