Tomography studies of coins shed light on the history of Volga Bulgaria


Image: Photographs of the investigated coins of ancient Volga Bulgaria: the Samanid multidirham (a) and the Bulat-Timur dirham (b). For the images of each individual coin, the corresponding scales are presented. On…
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Credit rating: Kazan Federal College

Kazan Federal College, Joint Institute for Nuclear Research (Dubna, Russia), and Khalikov Institute of Archeology (Tatarstan Academy of Sciences, Kazan, Russia) are doing work together to research the physical homes of the coins discovered on the territory of previous Volga Bulgaria.

This medieval state occupied a practical position on the Volga river amidst continental trade routes. Volga Bulgaria experienced a made financial state and considerable trade relations with neighboring areas. Hence, the neighborhood coinage was made, and coins minted in other areas had been in huge circulation as well. A big variety of numismatic finds at the excavation web pages of metropolitan areas and settlements confirms this. The coins discovered consist of useful historical details. The chemical composition of the coins can offer essential details about the silver ore deposits from which the coins are made, matching a particular historical interval and identifying fakes. The inside framework of coins can give new details on the complex elements of coin minting, these as metal cooling fee, minting methods, and floor silvering.

“We determine the chemical composition of the coins, as well as their inside framework: the existence of coatings, levels, and other compositional heterogeneities,” clarifies co-creator Bulat Bakirov. “To do this, we use the methods of neutron diffraction and neutron tomography. Neutron methods are totally non-damaging and have a variety of special attributes thus, they can be utilised to research particularly uncommon and useful archaeological artifacts.”

Scientific studies of silver coins by modern scientific methods are incredibly helpful. Firstly, this provides a greater knowledge of the framework and historical phases of the economic and complex improvement of medieval Volga Bulgaria. Next, there is the probability of reconstructing medieval technologies, which is of excellent importance both equally for historical science and for educational reasons. Thirdly, these scientific tests are handy for the improvement of the methodology of restoration and preservation of archaeological finds.

In this distinct paper, a 10th century Samanid multidirham and a 14th century Bulat-Timur dirham had been carefully investigated. It was proven that both equally examined coins consist of a copper-silver alloy. Nonetheless, the Samanid multidirham is characterized by a incredibly high copper content material–on typical, about fifty% of the entire quantity of the coin content. The spatial distribution of silver and copper in this coin is uneven, which can be involved with both equally the peculiarities of the original ore and with the processes that take place all through its coining. No outcrops of a high silver focus on the coin floor, which are attribute of the liquation processes, had been unveiled. In contrast to the multidirham, the Bulat-Timur dirham is composed pretty much totally of silver. The quantity content material of copper in this coin is very very low–five.two%. The information on this coin composition are in superior arrangement with the results of investigations of the Golden Horde coins of that epoch

In the close to potential, the crew plans to extend the assortment of examined samples. Of excellent fascination are other solutions from ferrous and non-ferrous metals, in distinct, ingots and blacksmithing squander. This sort of scientific tests will significantly raise the knowledge of metallurgy in this historical location.


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