Electrochemical Characterization and Dating of Archaeological Leaded Bronze Objects Using the Voltammetry of Immobilized Particles

The application of solid state electrochemistry techniques for the characterization and dating of leaded bronze objects is described. Characteristic voltammetric signatures of copper and lead corrosion products were used as markers of more or less prolonged corrosion periods. The proposed methodology was applied to samples from the Roman archaeological sites of Valeria (Spain) and Gadara (Jordan), Roman and medieval sites in Xàtiva (Spain), and modern statuary exhibited outdoors, on the campus of the Universitat Politècnica of Valencia, Spain, covering a time interval between the fourth to second century bc and the 20th century ad . For such samples, the ratio between the signals for copper and lead corrosion products decreased monotonically with the corrosion time. This variation was modelled on the basis of thermochemical and kinetic considerations, the experimental data being consistent with a potential rate law for the corrosion process.     

Petrography of ancient Indian lime plaster

Samples of ancient Indian lime plaster have not previously been analysed. Excavation of a seventh century AD baked brick structure provided the necessary samples for a detailed laboratory examination of plaster. The plaster samples were studied by chemical and petrographic methods. The probable sources of lime and sand were indicated by the mineralogy.     

An analytical study, using inductively coupled plasma (ICP) spectrometry, of samian and colour-coated wares from the Roman town at Colchester together with related continental samian wares

Over 200 sherds of samian and colour-coated pottery of late 2nd or early 3rd century date have been analysed by inductively coupled plasma (ICP) emission spectrometry. Most of this material was excavated at Colchester, England; the remainder is related East Gaulish material. Some clay samples were also analysed. The material divides, after multivariate statistical analysis, into 11 clusters. These accord well with known archaeological evidence and suggest assignments of origin where these are uncertain. In particular, the archaeological evidence for a link between Colchester and the Sinzig potters is supported.     

Healing images. Gems and medicine

The main purpose of magical gems was to secure divine protection, avert evil influences and heal various diseases. Some body parts are especially addressed, such as the stomach and the uterus. This concern seems to relate to ‘societal diseases’ also found in contemporary literature. How do these ‘healing pictures’ function? The analysis of the pictorial elements reveals different levels of therapeutic efficacy. Some images use visual plays upon words, others combine Egyptian and Graeco‐Roman elements, allowing ‘bilingual’ readings. The mnemonic function of images, charakteres and voces magicae also requires further investigations. Objects could transmit the memory of oral rituals and knowledge. The transfer of magical figures on other media is very rare, but when it occurs, as on a few medical devices, it may help us to understand the mechanism of medico‐magical performance, combining formalism and inventiveness.