A MULTI‐ANALYTICAL APPROACH FOR THE CHARACTERIZATION OF COMMODITIES IN A CERAMIC JAR FROM ANTINOE (EGYPT)*

This paper describes a multi‐analytical chemical study performed on the original, almost totally conserved, content of a small ceramic jar from the Antinoe archaeological site (fifth to seventh centuries ad, Roman Egypt) and now belonging to the archaeological collection of the Istituto Papirologico ‘Girolamo Vitelli’ (Florence, Italy). Scanning electron microscopy with an energy‐dispersive X‐ray spectrometer (SEM–EDX), Fourier transformed infrared spectroscopy (FTIR) and X‐ray diffraction (XRD) were all used to characterize the inorganic components of the archaeological material. The organic substances were analysed using FTIR, direct exposure mass spectrometry (DE–MS) and gas chromatography – mass spectrometry (GC–MS). The inorganic component essentially consisted of halite (NaCl). Among the NaCl crystals, lamellar elements were identified. They were chemically characterized by carbonato‐apatite and showed a concentric morphology typical of the scales of small fish. The most prevalent organic constituents of the sample were monocarboxylic acids, α,ω‐dicarboxylic acids, and cholesterol and its oxidation products. The organic material composition was consistent with the occurrence of lipids of animal origin. In addition, diterpenes related to pine pitch were also identified. The overall results suggest that the material recovered in the small ceramic jar found in Antinoe is a residue of fish‐based pickles such as garum, muria, allex and liquamen, which were commonly used in Roman times.     

QUANTIFICATION AND DISTRIBUTION OF LIPID IN ARCHAEOLOGICAL CERAMICS: IMPLICATIONS FOR SAMPLING POTSHERDS FOR ORGANIC RESIDUE ANALYSIS AND THE CLASSIFICATION OF VESSEL USE

Organic residue analysis has been performed on 62 reconstructed vessels from a single archaeological site (Rounds, Northamptonshire, U.K.). In order to establish regions of lipid accumulation within a vessel, sherds were sampled from different parts of a vessel, for example base, body and rim, and submitted to lipid extraction procedures. The techniques of high-temperature gas chromatography (GC) and GC/mass spectrometry (GC/MS) were then used to analyse the sherd lipid extracts. The quantitative results obtained show differential accumulation and preservation of lipid in various parts of the same vessel. This latter observation has serious implications for the sampling of potsherds for organic residue analysis. Furthermore, the amount of absorbed lipid varies quite considerably between vessel types. On this basis, a new method is proposed for classifying vessel use by comparing the concentration of lipid present in different parts of individual vessels.     

The Application of Steroidal Biomarkers to Track the Abandonment of a Roman Wastewater Course at the Agora (Athens,Greece)*

A subterranean, stone‐built, sediment‐filled culvert discovered during excavations at the Agora (Athens, Greece) was dated to the Roman period on the basis of its characteristic construction and associated finds, including coins. The location of the culvert relative to other adjacent watercourses and an ancient river bed suggested that the structure was a sewer. This was confirmed through a multi‐molecular biomarker approach based on analysis of the bile acids associated with sediment filling the sewer, using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The acid fraction contained predominantly deoxycholic and lithocholic acids, while the neutral steroid fraction comprised a complex mixture of Δ⁵ sterol and 5β‐ and 5α‐stanols, dominated by coprostanol, suggesting the presence of faecal matter of predominantly human origin. The concentrations of neutral and acidic faecal biomarkers were observed to vary in tandem, with the highest concentrations being found in the sediment at the base of the fill in the culvert. A reduction in concentration occurred with decreasing depth of the fill, with concentrations in the uppermost samples being little different from control samples of sediment taken beyond the confines of the culvert. The enhanced concentration of bile acids relative to 5β‐stanols compared with fresh human faeces must reflect the enhanced diagenetic stability of the former, thereby making bile acids the possibly preferred biomarker for this type of study. The quantitative data obtained suggest that the culvert fell rapidly out of use, possibly coinciding with the Slavic incursion in AD 582–3.     

How Did Mississippians Prepare Maize? The Application of Compound‐Specific Carbon Isotope Analysis to Absorbed Pottery Residues From Several Mississippi Valley Sites

A newly developed compound‐specific stable carbon isotope technique allows the detection of maize in absorbed organic pottery residues. This method was applied to absorbed organic residues from a variety of Mississippi Valley potsherds, and successfully identified maize components. Maize was cooked in sampled vessels less often than expected, but otherwise fitted expected patterns of maize use derived from stable carbon isotope analysis of human bone from the region. Absorbed organic pottery residue analysis is useful in determining pottery use, particularly in concert with other analytical methods.     

ARCHAEOLOGICAL AND CHEMICAL RESEARCH ON SEDIMENTS AND CERAMICS AT POLIDEPORTIVO (SPAIN): AN INTEGRATED APPROACH*

This paper proposes a preliminary approach to the integration of archaeological evidence and various chemical analyses (phosphorus and lipid) on sediments and ceramics. Phosphorus and organic matter analyses are, thus, used for the study of sediments, and lipid analyses for pottery from structure 19 of the Late Neolithic—Early Copper site known as ‘Polideportivo’, Martos, southern Spain. The results of both types of analysis point to a predominantly domestic function for this structure.     

IDENTIFICATION OF AN ADHESIVE USED TO REPAIR A ROMAN JAR

A combination of micro-analytical techniques, including thin layer chromatography (TLC), gas chromatography (GC), and combined gas chromatography/mass spectrometry (GC/MS), was employed to study the lipid composition of an adhesive used to repair an Ecton ware jar, recovered from Roman sediments of the River Nene at West Cotton (Rounds, Northamptonshire, U.K.). GC of the total lipid extract of the adhesive showed a complex pattern which was difficult to interpret. TLC was used to fractionate the extract. The fractions were then trimethylsilylated and submitted to GC and GC/MS. Betulin, lupeol, lupenone, allobetul-2-ene, and several other pentacyclic triterpenoid compounds were shown to be present in the ancient material. The similarities between the lipid compositions of the adhesive and of contemporary birch bark tar and a birch bark total lipid extract led to the conclusion that the adhesive was derived largely from birch bark, thus providing the first firm evidence for the use of birch bark tar in ancient Britain.     

Lipid Residues from Low‐Fired Pottery

This paper assesses the fate of lipids associated with low‐temperature and pit‐fired pottery to determine to what degree organic compounds persist or are removed during short‐firing episodes below 800 °C. Three different types of clay were fired using contrasting techniques including at 400 °C for 4 h in a muffle furnace, and pit‐firing in which pottery was fired to higher temperatures but for shorter periods of time. Total lipid extracts obtained by solvent extraction of test sherds were screened using gas chromatography‐flame ionization detection (GC‐FID) to determine the lipid concentrations and gas chromatography–mass spectrometry (GC–MS) to identify the organic compounds present. The results showed that firing of clay removes all naturally occurring alkyl lipids; however, during pit‐firing, diterpenoid lipids were introduced into the clay as a condensate from pine ( Pinus spp.) wood used as fuel. These results confirm that alkyl lipids, e.g., fatty acids, can be reliably associated with the use of vessels, although caution is required when interpreting the origins of lipids that might derive from fuel used in firing.