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Keywords: Cadmium Zinc Telluride (CZT), room temperature xadiation detectors, (PL), X-ray diffraction @D), pardcle-~duced X-ray emission (PIXE), crystal growt& ABSTR4CTVertical high pressure Bridgman (VHPB) Cdl-#UTe (0.04< x < 0.24) detector crystaIs grown m the Ukraine and Russia have been evahated and compared to U.S.-grown materials. Various analytical techniques were used to study the materials for trace impurities, precipitates, crystallinity, and electrical transport properties. Relatively high concentrations of carbon and trace impurities such as Se, Nd and Si have been detected in the crystals. In most cases, the crystals showed lower resistivity than U.S.-grown CZT. However, recent crystals grown in Russia exhibited better detector performance than those grown in prior years, and good response to an '*k radioactive source was found. Electron Metimes below 1 ps were measured in crystaIs having significant numbers of micro-defects, compared to lifetimes of 5-15 ps found in spectrometer grade materials produced in the U.S. Furthermore, the zinc composition along the growth axis showed better homogeneity m comparison with the U.S. material.