Finances and coinage in the reign of Trajan

This research project on the finances of the Roman state in the reign of Trajan (AD 98-117) carried out by B. Woytek has yielded ground-breaking results in many respects. It was characterised by an innovative interdisciplinary approach: On the one hand, all the literary and papyrological sources concerning the finances of the period were carefully collected and evaluated, on the other hand, the silver coinage of the period was used as a source of financial history for the first time in that a selection of Trajanic denarii was subjected to metallurgical analysis by means of micro x-ray fluorescence spectrometry. That was possible through a close cooperation with Prof. DI Dr. M. Schreiner, head of the Institute of Science and Technology in Art (Academy of Fine Arts Vienna), and his colleague Dr. K. Uhlir: In the course of the project, three denarii of the emperor Nerva (AD 96-98) and 67 denarii (as well as one drachm) of Trajan were analysed for the composition of their alloy. In order to circumvent problems created by the well-known phenomenon of "surface enrichment" in ancient silver coins, it was decided not to perform the analyses on coins from a public collection, but to acquire badly preserved denarii especially for the research project from coin dealers. These coins could be analysed with a destructive method: The denarii were cut in two and the composition of the alloy was analysed on the surface of the cut, in the very core of the coin. This was the only way to obtain scientifically reliable results: In the course of our project, the majority of the data concerning the composition of Trajanic denarii published up to now could be shown to be inaccurate. Those results had been obtained by surface analyses and are marred by the higher silver content of the layers on (and below) the coin surface, a phenomenon possibly caused by metal corrosion. The exciting new data obtained in the research project are coherent and tie in well with what could be found out about the financial history of the period: At the beginning of Trajan`s reign, in AD 98 and 99, the silver content of the denarii was the same as under Nerva, about 85 to 94 %. Suddenly, in AD 100, the standard was reduced to 80 % ca., and to this the Roman mint adhered until AD 117. The reduction is probably to be interpreted in the context of the preparation of Trajan`s first Dacian war (AD 101-102). Since it was at the end of 99 that Trajan entered Rome for the first time after coming into power, it may be surmised that the decision to reduce the standard was made by the emperor himself or his entourage.