Roman coins

Roman coins were borrowed from G. Carter who had filed down one side of the coin for x-ray fluorescence analysis. The inner samples were taken from this filed-down side of the coin. The x-ray analysis data of Carter for each of these five coins were within dbl.5% silver of that found by the streak method. 

It is difficult today to determine what value such coins had in ancient times, but it is certainly apparent that these were the small change of their era and locale. Roman coins were available and used throughout the Roman Empire, but these coins were used within the smaller, localized area of influence of the Herodian kings (2). Whether Herodian coins were used in other transactions besides those involving the Temple treasury is also difficult to determine exactly. But it seems logical to conclude that there was most likely other local, commercial uses for such coinage as well (I, 2). 

Although Chapter 10 describes a study aimed at elucidating early technological methods, the research presented in Chapter 11 by Carter and Razi shows how the analysis of coins can provide historical political information. This chapter is the latest in a series of chemical studies of Roman coins that have been included in the earlier volumes of the Archaeological Chemistry series. These studies have shown how coins were produced and how early Roman mints functioned. Chapter 11 shows how the political fortunes of the Roman Empire affected the composition of the coins. Debasement of the coins reflected periods of political turmoil. 

Zinc was detected only at very low concentrations in most Republican coins. It was usually present as a trace impurity. However, two coins were deliberately made of brass the earlier one was made by Julius Caesar. These are the earliest known Roman coins made of brass (13). Brass was a new and rather expensive alloy because it was necessary to make it by diflusion of zinc vapor into copper. Zinc was not prepared in metallic form by the Romans or other ancient peoples because of its volatility. 

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... 

Early Republican coins are remarkable for their high cobalt contents and many for their exceptionally high lead, arsenic, or antimony contents. The cobalt contents are uniquely high in early Republican coins compared with all Roman coins made from about 135 B.C. to A.D. 400. Some late Imperial Roman coins contain high amounts of lead, but not as high as in the early Republican semisses and asses. 

In this connection it is interesting to note that Roman coins and other bronze objects which were thrown into certain thermal springs as votive offerings and have since been examined are found to have become partially converted into various sulphides of copper, including chalcopyrite and erubescite. 

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

Much other information has been obtained by analyzing Roman coins... 

Since Roman coins were struck by hand using two separate dies, the relative orientation of the obverse (heads) and reverse (tails) dies is variable. If the obverse is normally oriented with the bust facing left or right, the obverse is oriented at 12 00 (the major vertical axis points in the direction of the hour hand at 12 00). If the coin is rotated 180° around the 12 00 axis, the major vertical axis of the reverse may now point in any direction, and the relative orientation is given as the direc-... 

Roman coins were individually hand struck from heated blanks using two hand-tooled dies, a fixed anvil die for the obverse, and a second. 

Chemical analyses and physical measurements of a large number of Roman coins struck in four years have produced the following observations and conclusions ... 

Roman Coins II. Augustus and Tiberius, American Numismatic Society... 

Metcalf, W. E., Roman Coins from the River Liri. II, Numis, Chron,... 

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). 

The following three paragraphs contain examples of knowledge gained through determination of the major and trace element compositions of Roman coins ... 

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

The quadrans was the lowest denomination of Roman coins slightly worn quadrantes have roughly about the same weight as a U.S. penny, a little over 3 g. Quadrantes, however, are usually smaller in diameter... 

Comparison of Compositions with Those of Other Roman Coins of About the Same Age... 

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