Abstract
Gray pottery is one of the most significant and important cultural artifacts discovered from the Bronze Age sites in the southeast of the Iranian plateau. This style of pottery has been obtained in a very large amount from the Chagardak Asr-e-Faraghi site of Chah Hashem Plain in Baluchistan, which has so far been far from the views and studies of archeology, archeology and artistic history of the southeast of the Iranian plateau. The main question of this research is about how to make and decorate these pottery. It seems that pottery making was developed in this area and they had different construction methods. The present research has been done by analytical-experimental method and based on laboratory studies. The studied objects belong to the Museum of Southeastern Iran. Measures such as documenting the condition of objects as well as sampling necessary for laboratory tests have been performed at the restoration workshop of the Museum of Southeastern Regions of Zahedan. Then, using thin section petrographic studies (OM) and instrumental analyzes with SEM-EDX and XRD methods, the data are analyzed in order to achieve the research objectives. In this study, 11 samples of gray pottery related to Chegardak area, which were obtained from emergency excavations in 2018, were performed. All pottery was wheeled and gray in dark to light and with different thicknesses but in the range of thin pottery. Archaeological studies on pottery suggest a similar composition, but show that different production methods were used. The pottery in question was pottery produced in high heat furnaces and advanced methods such that precision in construction, elegance and strength were considered by the potters. The results show that pottery in this area has been a very advanced industry that has used iron and manganese-based minerals to decorate the pottery.
Keywords:  Archeology, Petrography, Bronze Age pottery, Chegardak, SEM-EDX, XRD.

Introduction
Southeastern Iran is one of the most important and prominent regions in terms of human evolution in the Bronze Age. Evidence of this is the dispersion and existence of numerous ancient sites and hills related to the third millennium BC in this area. Significant sites such as Burnt City (Tosi, 1976; Biscione et al., 1977; Piperno & Tosi, 1975; Tosi, 1968) ¬, Bumpur (DeCardi, 1968; Mortazavi, 2004; 2006) 2018), Speedge (Heidary et al., 2019), Khorab (Stein, 1937) and Domain (Tosi, 1970) as well as Chegardak area (Heydari et al, 2015) are prominent and prominent examples in Sistan and Balochistan, all of which have been studied and various archaeological studies to date Chagardak Archaeological Site (27 ° 5’14 ‘’ N; 59 ° 7’8 ‘’ E) is located in Delgan city and Dasht-e Chah Hashem village, 10 km northeast of Chagardak village (200 km west of Iranshahr city). This area takes its name from the nearby village, namely Chagardak. This area is located in a flat and low plain. The ancient site of Chagardak in the plain of Chah Hashem Jazmourian includes a hill and two cemeteries related to the Bronze Age of Balochistan. This area has been in turmoil and damaged in 2005 due to extensive destruction and looting by traders. During the salvage excavations carried out in 1397, the Archaeological Department of the General Directorate of Cultural Heritage of Sistan and Baluchestan Province discovered a variety of artifacts, including pottery painted in pea, gray and red. Gray pottery is one of the most important finds from the lesser-known Chagardak site in Balochistan. Therefore, these findings have been analyzed and studied in this pilot study using petrographic, SEM-EDX and XRD methods. In the first stage, petrographic analysis was performed on all pottery. In the study of pottery petrography, a very important issue is the materials added to the pottery paste. All the pottery is wheeled and gray in the range of dark to light and with different thicknesses, but within the fine pottery of this region. Samples were named based on the first letter of the name of the Chagardak site in Latin (CH) and the sample number from 1 to 11. Among these specimens, numbers 1 to 8 are broken and small pieces of pottery obtained in the excavations of this area, and numbers 9 to 11 are pottery that is much more complete and with Ability to perform restoration operations (Table 1). Gray painted pottery is one of the types of pottery that has been obtained in many areas of southeastern Iran. Their designs are taken from the ecology of the region and the culture of the people of that period. Scanning electron microscopy analysis equipped with X-ray fluorescence analysis (SEM-EDX): for microscopic examination of the pottery matrix, identification of minerals as well as melting and vitrification stages of the pottery, as well as identification of the chemical composition of the matrix and minerals. SEM-EDX method was used. The SEM device used is the MIRA3 model made by Tescan, an American product. Also, to identify the composition of pigments used in painting ceramics, the EDX elemental method and the VEGA / TESCAN-XMU model made in the United States, which was coupled to the above SEM machine, have been used. The resolution was 1.5 mm at 15 kV and 4.5 nm at KV1 with BSE detector. Also, the method used in this research is point analysis. The mentioned experiment was performed in Razi Metallurgy Laboratory of Tehran. X-ray diffraction (XRD): X-ray diffraction method has been used to identify crystalline phases and mineralogical studies in the desired pottery. The model of the device used is X’spert Prompd Panytical made in the Netherlands, which has been done in Razi Metallurgical Laboratory of Tehran. The samples were analyzed at 30 Ma current and 40 Kv voltage. Information on the identification of crystal phases based on PDF2 database was reviewed and obtained by Xpert High Score Plus software version 2010. Therefore, how the art of making and recognizing the pottery industry in this region can be one of the most important questions and goals. Therefore, in this research, we have tried to answer some questions such as the following questions by using some common methods of analysis in the archeology of ancient pottery. A) What kind of mineralogical composition does the pottery discovered from Chegardak have? B) Structural and archaeometric studies of ceramics show what kind of process shows in the way of making and baking pottery?

Conclusion
These experiments showed that the pottery has a very dense, hard and non-porous texture, which shows that the prehistoric potters of the Chagardak area five thousand years ago were very precise and skilled in the type of drilling and processing method. So that no emptiness or signs of improper weaving can be found in the pottery. This point should be considered as one of the most important features of gray pottery in this region, especially in the southeast of Iran. On the other hand, the resulting studies show that the soil used in the manufacture and production of pottery paste is very desirable, washed and free of any additives. As their strength is so high after firing that they can not be easily broken, this can be seen well in the type of sintered and semi-glass texture of pottery. Also in XRD phase analysis, the presence of high heat phases was detected. It is very likely that high heat furnaces using regenerative conditions were used in the construction of the pottery. On the other hand, in the archeological excavations and emergency excavations carried out by the archeological group of the area under the supervision of Mohammad Heydari, the architectural remains of a pottery kiln, molten pottery and kiln were discovered, which shows this. This industry has been an art and native production of the people of this area. The last stage of producing a pottery was the methods of polishing and decorating it to produce a magnificent work of art. Elemental studies showed that the prehistoric painter and craftsman of Chagardak used iron-based minerals such as hematite and red recently to record red colors, and a combination of iron-oxide and manganese-based materials to produce black and dark colors.

The depiction of camel fighting in rock art to express certain rituals of human can be traced back to the late Paleolithic period and is believed to have originated in present-day northwestern Kazakhstan. After the domestication of Bactrian camels, depictions of camel fighting developed a relatively standardized format, primarily presenting paired camels engaged in aggressive biting matches. This motif of camel fighting may have originated in the Karate and Baikonur regions of Kazakhstan during the Bronze Age. Due to geographical proximity, the custom of camel fighting was introduced to the Sarmatians in the Ural steppes early on, and through the Sarmatians, it spread to the Huns (Xiongnu) in the north and the Qiemo people in Xinjiang, China, and later to Kangju. The camel fighting depicted in the Sulaek petroglyphs in the Minusinsk Basin should be attributed to the Kyrgyz, and its origin is likely the Huns. The fighting camels in the Loulan mural tombs may have been inherited from Qiemo or originated from the Huns. The camel fighting motif in Persian miniature paintings first emerged during the Timurid period in the latter half of the 15th century CE. The Timurid Empire was founded by Timur, a noble from the Barlas tribe historically affiliated with Mongol aristocratic lineages. This Central Asian polity maintained profound Mongol cultural influences. Notably, camel fighting had already been practiced as courtly entertainment in the Yuan Dynasty (established by the Mongols) as early as the first half of the 14th century CE. This chronology demonstrates that the Mongols long upheld camel fighting rituals, and the motif in Persian miniatures was transmitted westward through Mongol cultural and political influence.

The preserved 6-7th century portraits of royal supporters from the Kucha Caves in Xinjiang show a “patterned” costume and appearance, especially the “standing on tiptoe” posture and the pictorial structure of multiple figures standing side by side, which have a strong connection with Iranian and Central Asian art. The unique “standing on tiptoe” style of the Kucha Grottoes mural depicts a donor pattern that is neither found in the painting and sculpture of Dunhuang or other regions of China, nor seen in Gandhara reliefs, Parthian art, or Near Eastern art of the Parthian period. However, is frequently seen in painting and sculpture from Iran to Central Asia between the 3rd and 7th centuries AD. The origin of the art of Iran and Central Asia the forms of expression are related to the construction of royal identity, religious rituals, and the viewing habits and aesthetic concepts of the people of Kucha. The small number of inscriptions preserved in the Kucha Caves on the donor’s figures indicate that these Kucha kings were real people, and it is highly likely that the painters had met them. However, the way the feet of the figures are drawn is not realistic, but rather stylized, creating a perfect visual pattern that transcends ordinary reality, indicating that the painters were aiming to present all the Kucha kings as an “idealized” manner. The pictorial pattern of “standing on tiptoe” posture influenced by Iranian Sasanian and Central Asian Sogdian art is evident. 

The rise and migration of the Hephthalites left a significant impact on the exchange of East-West civilizations, and the empire they established was one of the inevitable problems in the study of Silk Road. The period from the end of 5th century to the early 6th century was the zenith of Hephthalite Empire when the alliance between Hephthalites and Sasanians was established and the Hephthalites expanded to Tarim Basin and southward to North-West India. The Hephthalite Empire played an important intermediary role in the interaction of East-West civilizations, ensuring the stable development of the Silk Road in the 5th and 6th centuries and laying the foundation for the prosperity of the Silk Road during the Sui and Tang Dynasties. The Chinese Northern and Southern Dynasties observed the Hephthalites in China and noted their interactions with different ethnic groups, such as the Han Chinese, Sogdians and Persians. Chinese written sources such as the Book of Wei, the Book of Zhou (Zhoushu 周书), the Book of Liang (Liangshu, 梁书), the History of Northern Dynasties (Beishi, 北史), the Book of Sui (Suishu, 隋书), the New Book of Tang (Xintangshu, 新唐书) as well as Comprehensive Statutes (Tongdian, 通典), provide substantial information about the Hephthalites. With the advancement of archaeological discoveries in recent years, the Hephthalite coins and Persian coins have also become crucial numismatic evidence for understanding the Hephthalite activities in medieval China and their relations with different ethnic groups in China and along the Silk Road.