| Abstract: | X-ray fluorescence analyses of ten Septimius Severus denarii, all having the catalog number Cohen 777, and all minted in a.d. 196, show the following: (1) copper and silver concentrations in the ten coins cover a rather broad range, (2) lead and gold concentrations correlate with the silver concentrations, (3) no elements, except silver, correlate directly with the copper contents, (4) two coins have very nearly the same compositions, but this could actually be explained by chance, given the precision of the analyses and the range of compositions found for all ten denarii, (5) weights, thicknesses, and diameters of the coins varied over a relatively wide range, but densities varied only slightly. Assuming reasonably homogeneous melts of coinage alloy, X-ray fluorescence (XRF) analyses of many more Severus denarii of a.d. 196 should enable one to deduce several details of the mint operation such as (1) the number of dies in use of C. 777 coins at one time, (2) the overall batch size of coins, and (3) the number of different Severus denarii minted from the same batch of alloy. With improved precision of XRF analyses now possible, it only remains for a source of Severus denarii to be found to enable testing of this hypothesis. |
