Scientific advances in the laboratory testing have provided the most effective means for archaeologists to examine their artifactual data in a science-based framework. In this research project we have been able to examine 30 ceramic samples from two archaeological sites with the homogeneous ceramic horizon.
North-central Iran, approximately the area lying between Kashan, Qazvin and Tehran is, characterized by uninterrupted plains watered by streams from the neighboring mountain ranges. As there are no major geographic barriers, in many periods ceramic assemblages were identical throughout the area. Finely made painted ware characterizes the upper part of Cheshmeh Ali IA and has been found at Qara Tepe and Esmailabad Tepe west of Tehran in the upper levels at Zagheh at Saveh and in Sialk II. It occurs in a variety of shapes including cup bowls, spouted bowls, hemispherical and closed bowls, shallow and deep bowls on pedestal feet, basket-handled pot and concave-sided cups. Cheshmeh Ali ceramic horizon is hand-made of fine grained fabric and covered with a burnished orange-to-red slip and painted in black on red. A wide variety of designs include lozenges hatched triangles, festoons, chevrons braided patterns and stylized animals and fish. It is especially well known from the excavations carried out at Tepe Esmailabad. The material from this site seems more elaborate than that of Zagheh. In spite of the facts that all the examined samples belong to the same ceramic horizon in the area XRF and XRD, laboratory testing has indicated certain technological differences between two groups of samples.