Coins copper-base Roman

From about 150 to 80 B.C., most of the coins contained much higher silver concentrations than normally found in copper-based Roman coins (see Figure 7). There is no indication that silver was deliberately added to any... 

Chemical Compositions of Copper-Based Roman Coins. Augustan Quadrantes, ca. 

SEVERAL HUNDRED COPPER-BASED ROMAN COINS have been analyzed by wet chemistry (J-5), x-ray fluorescence spectroscopy (6-11), and atomic absorption spectroscopy (12). Consequently, a general understanding of the compositions of copper-based Roman coins is developing. For instance, the debasement of orichalcum (Roman brass) coins by substituting tin and lead for zinc during the late first and second centuries is well known (1,12). 

This chapter is the seventh in a series of articles on the chemical composition of copper-based Roman coins. 

Chemical Composition of Copper-Based Coins of the Roman Republic,... 

Twenty-two copper-based coins of the Roman Republic were analyzed for Fe, Co, Ni, Cu, Zn, As, Ag, Sn, Sb, and Pb by using X-ray fluorescence according to the procedures described by Carter and Booth (11). Generally, X-ray fluorescence determines elements only in a thin surface layer, about 5-10 xm deep, so it was necessary to clean coins for analysis in such a way that the surface layer was as representative of the entire coin as possible. First, the coins were cleaned by electrolytic reduction in a hot solution of sodium carbonate. Next, the coins were abraded in an air stream containing finely divided aluminum oxide powder to remove about 10 to 15 xm of metal. Carter and Booth described the cleaning procedure in detail as well as the X-ray fluorescence parameters (11). 

Additional analyses are required before one may reliably conclude that chemical composition correlates with denomination. There are indications that composition correlates with denomination (e.g., the exceptionally high lead contents of mid-second-century B.C. semisses and asses and the low lead contents of quadrantes). However, larger numbers of coins must be chemically analyzed to obtain a thorough understanding of the Roman Republican copper-based coinage. 

The as was the largest denomination of copper-based coins of the Roman... 

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