Archaeological Analysis of the Elymais Coins in the Interval (85BC-AD224), with a Political and Economic Approach, Based on Elemental Analysis of Coins: PIXE Spectroscopy

The Elymais, as a semi-autonomous and sometimes autonomous satrap, had a special place in southwestern, western, and southern Iran at the same time as the Seleucids and Parthians. This rule has played an active political and economic presence in the region from the middle of the second century BC until the rise of the Sassanid Empire, simultaneously with the Seleucid and Parthian rule. Most of the Parthian monuments are located in the Elymais geographical region and many of the traditions that were manifested during the Sassanid period have been the main achievements of Elymais culture. Despite the wide range of artifacts identified during this period, many aspects of the Elymais rule are still unknown. Coins as useful and index data in archaeology, due to their durability and frequency, by studying motifs and texts, provide valuable information about different periods. In addition, the use of laboratory science on these findings provides useful supplementary information for researchers. In this article, a collection of bronze and silver coins belonging to the Elymais period were studied by the PIXE method, in order to answer the questions about the concentration or purity, the number of mines, the number of mints on these coins, and the appearance of these compounds in understanding the economic and political structure of the period. To achieve these purposes, 35 coins from the Elymais were analyzed. These coins ranged from 85 BC to the early third century AD. The results showed that the analyzed coins were minted in six mints (two mints used in each of the three periods) and their raw material was different from the three mines. On the other hand, the ratio of the percentage of the main elements of coins in the three Elymais periods are different and the decreasing trend of silver and copper percentages and the increasing trend of lead percentage in the analyzed coins indicate a better coin minting situation in the first Elymais period than the second and third periods, and the better political and economic situation of the kings of this period; In addition, the domination of the Elymais over Susa had a direct effect on the purity and better quality of their coins.
Keywords: Coin, Elemental Analysis, PIXE, Political and Economic Situation, Elymais.
 
Introduction
The Elymais rule in the mountainous region of Bakhtiyari and the low and alluvial land of Khuzestan was present at the same time as the Seleucids and the Parthians and played a significant role in the historical events of the region. Elymais is the main place of Parthian art and has played a special role in the formation and development of various cultural aspects and their transfer to the Sassanid era. Historical documents state the names of various areas, cities, and temples in the Elymais realm, and archaeological studies have identified more traces of the rule. However, understanding the Elymais rule is still in its infancy. In the historical documents of the late third century BC, the Elymais are mentioned, but the founder of this rule was, in fact, Kamnaskires the First (140-160BC), and the Elymais rule had an active presence in the events of this region until the beginning of the Sassanid Empire. The name “Elymais” in Greek is the same as the name “Elam” in the Semitic language, which has been used interchangeably in various Babylonian inscriptions. Various divisions have been mentioned about the period of the Elymais rule and the order in which its kings came to power, which indicates the lack of primary and key information in this period. Study resources to identify the Elymais are archaeological data, historical documents, and interdisciplinary sciences. At present, based on the coins of this period, as a finding with a significant quantity and comparison with other data, a more accurate sequence of the rule of the Elymais kings can be identified. Accordingly, the Elymais rule after the coming to power of Kamnaskires can be divided into three periods: The Kamnaskires dynasty (160/140BC-AD25), the Parthian dynasty (AD25-150), and the reign of the last Elymais kings (AD150-221). On the other hand, among the interdisciplinary sciences used in archaeology is archaeometry, which is used to identify elemental compositions and origin-finding, reconstruct and study on technology, regional and extra-regional trade, the political and economic situation of ancient societies, and date objects and sites. In this article, we try to deal with the elemental analysis of 35 coins of the Elymais kings by the PIXE method, and to answer the question of how the percentage of elements in coins can help us identify the number of mines, mints, and the analysis of political and economic situation of the Elymais rule.
 
Discussion
In this study, 2 silver coins and 33 copper coins belonging to different Elymais kings were elementally analyzed by PIXE method in the “Vandograph” laboratory of the Atomic Energy Organization of Iran. The oldest coins analyzed in this study belong to Kamnaskires IV and Queen Anzazeh, and the newest coins analyzed belong to the seventh unknown king. The coins before the analysis were classified into two categories, silver and copper, but after the analysis, the coins in which the silver was more than 50% were classified as silver coins, those with 3 to 49.9 percent silver were classified as Bilon coins, and those with less than 3 percent silver were classified as copper coins. By analyzing these 33 copper coins, it was determined 8 Bilons and 25 copper coins (2 silver coins, 2 copper coins, 5 Bilon coins related to the first period, 11 copper coins and 3 Bilon coins related to the second period and 12 copper coins related to the third period). It is not possible to say with certainty whether the Bilon coins were more valuable than other copper coins, or whether the Bilon coin was a special style of coinage by the Elymais, but among the analyzed coins, especially in the first period, there is the minting of Bilon coins. Since the percentage of copper to lead in these coins is different and this can confirm different mints, it may be possible to suggest the generality of this style of coinage (Bilon) for the Elymais. During the Parthian dynasty, this style of coinage (Bilon) was not seen, and during the time of Kamnaskires Orod the first, which completely reunited Susa and Elymais, the Bilon was seen again.
 
Conclusion
Based on elemental analysis, the decreasing trend of silver and copper percentages and the increasing trend of lead percentage in the analyzed coins indicate a better situation of coinage in the first Elymais period than the second and third periods and better political and economic situation of the kings of this period. According to the percentage of copper to lead, it can be stated that the coins were minted in six different mints and two mints were active in all three time periods. Considering the percentage of calcium in the coins, we can mention the use of three different mines to extract ore to produce these Elymais coins. The increase in lead in silver and Bilon coins confirms the changes over three periods, and this increase has been due to the reduction of available copper mines or the need for rapid coinage or re-smelting. It seems that the presence of the Parthians in the Elymais region was as an external factor that created a gap between the Elymais bases in the highlands and low plains of Khuzestan (especially Susa) in access to resources and their integration and caused a decrease in the purity of coins. When these two regions were under the control of the Elymais rule, they could have mastered the capabilities of the highlands and low plains and used them, which has been reflected well in the results of the coin analysis.