THE PROVENANCE OF IRON ARTEFACTS FROM MANCHING: A MULTI‐TECHNIQUE APPROACH*

Iron finds from the Celtic oppidum of Manching in southern Bavaria (Germany) are analysed in view of their possible provenance. The exceptional size and the location of Manching are usually attributed to the presence of abundant iron ores in its vicinity. After a review of previous approaches for source determination of iron artefacts, we introduce lead isotope analysis as a new approach. However, only by combining the trace element patterns of slag inclusions and iron metal with lead isotope ratios in the metal is it possible to distinguish various iron ore formations near Manching. As a result, it turns out that, indeed, the most obvious ones—namely, bog ores near the Danube—constituted the main resources for iron production at Manching. It was even possible to select one occurrence as the most likely ore source.     

A Study Of The Firing Technique Of Pottery From Kaman‐Kalehöyük,Turkey, by Synchrotron Radiation‐Induced Fluorescence X‐Ray Absorption Near‐Edge Structure (Xanes) Analysis*

Fe K‐XANES spectra of a series of pottery sherds excavated from the archaeological site of Kaman‐Kalehöyük, Turkey, were measured to reveal the firing technique of the pottery. The analysis disclosed relationships among the chemical form of the iron, the firing conditions and the colour of the pottery. The pottery referred to as ‘Grey Ware’ found at this site was classified into two groups according to the chemical form of the iron. Also, it was revealed that the Iron Age pottery referred to as ‘Cream Ware’ was produced first under reducing conditions, and then fired under oxidizing conditions.     

THE USE OF TRACE ELEMENT ANALYSIS OF ENTRAPPED SLAG INCLUSIONS TO ESTABLISH ORE – BAR IRON LINKS: EXAMPLES FROM TWO GALLO‐ROMAN IRON‐MAKING SITES IN FRANCE (LES MARTYS,MONTAGNE NOIRE,AND LES FERRYS,LOIRET)*

Knowledge of the iron trade in ancient times rests on determining the source of the objects recovered during archaeological excavations. Unfortunately, attributing the origin is not always possible using archaeological tools alone. Trace element data of the ore and the archaeological material (reduction and reheating slags, entrapped slag inclusions from the bloom, bar iron and iron blades) from two Gallo‐Roman iron‐making centres, Les Martys (Montagne Noire) and Les Ferrys (Loiret), were determined using ICP–AES/MS and LA–ICP–MS. The results highlight a continuity of composition that makes it possible to establish a link between the initial ore and the semi‐finished iron products.     

TRACING THE RESOURCES OF IRON WORKING AT ANCIENT SAGALASSOS (SOUTH‐WEST TURKEY): A COMBINED LEAD AND STRONTIUM ISOTOPE STUDY ON IRON ARTEFACTS AND ORES*

Lead and strontium isotope analyses were performed by thermal ionization mass spectrometry (TIMS) on Roman to Byzantine iron artefacts and iron ores from the territory of ancient Sagalassos (south‐west Turkey), to evaluate Pb and Sr isotopes for provenance determination of ores for local iron production. It can be demonstrated that for early Roman artefacts and hematite iron ore processed in early Roman times from Sagalassos proper, as well as for magnetite placer sands and early Byzantine raw iron from the territory of the city, Sr isotopes are much less ambiguous than Pb isotopes in providing clearly coherent signatures for ore and related iron objects. Late Roman iron objects were produced from iron ores that as yet remain unidentified. Early Byzantine iron artefacts display more scatter in both their Pb and Sr isotope signatures, indicating that many different ore sources may have been used. Our study demonstrates that iron objects can be precisely analysed for their Sr isotopic composition, which, compared to Pb isotopes, appears to be a much more powerful tool for distinguishing between chronological groups and determining the provenance of raw materials.     

Cargoes of Iron Semi‐Products Recovered from Shipwrecks off the Carmel Coast,Israel

Underwater surveys along the Israeli Carmel coast have revealed six cargoes of iron semi‐products associated with shipwrecks. They are described and dated according to the associated artefacts. Metallographic and chemical analyses on samples from the biggest cargo have determined the stages of the chaîne opératoire, identified the properties of the iron and characterized the iron trade along the Israeli coast. The new discoveries contribute to our understanding of the circulation of iron in the South Levant, which was characterized by an almost complete absence of local iron production. During the Byzantine and Crusader periods, this absence was compensated by long‐distance sea trade, depending on political circumstances and restrictions. Three main types of iron semi‐products were identified: (a) partly consolidated blooms, (b) short pointed bars and (c) elongated pointed bars. The cargoes discovered represent a time period of nearly a millennium. Altogether, 148 iron semi‐products were studied. Of these, 166 were from cargo a, which was dated by coins to around 1130–1200 ce . Those coins could have been imported from Europe for Crusader military and civil uses in the Levant. The iron from cargoes b, d and f, dated perhaps to the Byzantine period, could have been imported from Anatolia or Venice for military and civil purposes.     

THE TECHNOLOGY OF ‘GLAZED’ RESERVED SLIP WARE—A FINE CERAMIC OF THE HARAPPAN PERIOD*

‘Glazed’ Reserved Slip Ware (RSW) is a high‐quality glossy bichrome pottery of the Indus Valley civilization, and dates to the mature Harappan period (c. 2600–1900 bc ). Scanning electron microscopy with energy‐dispersive X‐ray analysis indicates that the surface coat on RSW is composed of a pale grey vitrified clay slip, which overlies a black slip with significantly higher iron oxide. Hence the term ‘sintered’ Reserved Slip Ware is to be preferred. X‐ray diffraction analysis indicates that both the pale and black slips contain hercynite, mullite and quartz, but observation by scanning electron microscopy shows that the black slips contain higher amounts of coarser‐grained hercynite. The elemental data suggest that different clays were used to make the bodies and the slips. However, key element ratios are very close in associated black and pale slips. The grey slip may have been produced by elutriation of the fine, iron oxide‐rich clay that was used to prepare the black slip. The pale grey slip was laid over the black and removed by combing to produce a bichrome effect, which evoked semi‐precious materials such as agate. RSW was a specialist product that required significantly higher input skill and resources than the majority of Harappan clay‐based ceramics. It is a further example of the range of sophisticated Harappan ceramic wares, which included faience, fired steatite and stoneware.     

Iron mineralization and dolomitization in the Paran Fault zone,Israel: implications for low‐temperature basinal fluid processes near the Dead Sea Transform

Petrography, Eh‐pH calculations and the stable isotope composition of oxygen are used to interpret geochemical processes that occurred during iron oxide mineralization and dolomitization along the Menuha Ridge segment of the Paran Fault, southern Israel, adjacent to the Dead Sea Transform (DST). Iron mineralization is strongly localized in the fault zone as ferruginous lenses, whereas Fe dolomitization spreads laterally into the Cenomanian‐Turonian carbonate host rock as stratabound beds. The average oxygen isotope fractionation between syngenetic quartz and iron oxides in the ferruginous lenses gives a temperature of 50 ± 10°C and δ¹⁸O SMOW water = ?3.5‰; consistent with an origin from metalliferous groundwater flow in the sedimentary basin. Ferroan dolomite initially formed under strongly reducing conditions, but this was followed by oxidation and pseudomorphic replacement of the dolomite by a mesh of fine‐grained iron oxides (simple zoned dolomites). This cycle of ferroan dolomite formation and replacement by iron oxides was repeated in complex zoned dolomites. Dolomite oxygen isotope compositions fall into two groups: a high δ¹⁸O group corresponding to the simple zoned dolomites and non‐ferroan dolomites and a low δ¹⁸O group corresponding to the complex zoned dolomites. Water‐rock calculations suggest that the epignetic dolomites formed under fluid‐buffered conditions: the high δ¹⁸O group are indicated to have formed at temperatures of ca. 25°C for waters with δ¹⁸O = ?4 to 0‰; the low δ¹⁸O complex zoned dolomites at 50–75°C for waters with the same isotopic composition. A kinetic calculation for a complex zoned dolomite‐bearing bed indicates that dolomitization must have occurred at high values of the dolomite saturation index. This requirement for high Mg supersaturation and the indication that epigenetic dolomitization is more protracted in stratigraphically deeper formations located closer to the DST is consistent with models proposing that Mg‐rich solutions originated in the Dead Sea Rift.     

REGIONAL VARIATIONS IN BLOOMERY SMELTING SLAG OF THE IRON AGE AND ROMANO‐BRITISH PERIODS*

This study highlights regional variation in the composition of iron‐smelting slag produced in England prior to the medieval period and attempts to link slag composition to the type of ore smelted. For many sites, the slag compositions were consistent with the use of limonite ore, but there is evidence that siderite ore was smelted at sites in Sussex in the late Iron Age/Romano‐British periods. A compositional comparison of smelting slags and slag inclusions in Iron Age currency bars, using data from Hedges and Salter (1979 ), illustrates the potential of smelting slag compositional data in provenance studies of early iron objects.     

ESTIMATION OF THE AGE OF A PRE‐INDUSTRIAL IRON SITE IN KOREA*

A pre‐industrial iron‐smelting site in Korea, whose period of active use is placed on typological grounds between the eighth and 18th centuries ad , has been dated using accelerator mass spectrometry and thermoluminescence. The ages of two charcoal samples were 77 ± 25 and 81 ± 25 years bp , with the calibrated date for both ranging from ad 1700 to ad 1955, while a clay fragment dated to ad 1650 ± 50. The results from typology and radiocarbon seem insignificant due to the considerable uncertainties involved, but in combination with the thermoluminescence result they place the most probable date of the site at around ad 1700.     

Fracture‐focused fluid flow in an acid and redox‐influenced system: diagenetic controls on cement mineralogy and geomorphology in the Navajo Sandstone

Differential cement mineralogy is influenced by depositional textures, structural deformation, pore fluid chemistry, and ultimately influences landscape evolution by introducing heterogeneities in erodibility. In Southern Utah, the region West of the Kaibab uplift known as Mollies Nipple (Mollies) in Grand Staircase‐Escalante National Monument exhibits a complex history of fluid–sediment interactions, which has resulted in a localized zone of anomalous diagenetic iron sulfate (jarosite) mineralogy in a well‐exposed dune–interdune deposit within the Navajo Sandstone. Mineralogy and geochemistry of cements within this region are examined using reflectance and imaging spectroscopy, field investigations, microscopy, and whole‐rock geochemical analyses. These data show that the in‐situ jarosite cement is localized to a plane along the highest ridge of the butte, providing an armor along with other secondary cements, which controls the butte's geomorphic evolution. The jarosite cement is associated with other mineralogies suggesting that the sulfate was one of the latest fluid‐related precipitates in the paragenetic sequence. It was preceded by a regional bleaching event, precipitation of clay cements, some localized concretionary iron oxide precipitation, and formation of deformation bands. At least one generation of dense iron oxide mineralization is associated with cataclastic brittle deformation predating the sulfate precipitation. Trace element geochemistry of cements shows certain metal oxide populations associated with extremely high (>2000 ppm) arsenic values. We interpret the combination of spatial mineral distribution, observed paragenetic sequence, and trace element geochemistry to suggest this region experienced acid sulfate diagenesis along fracture‐controlled fluid conduits related to weathering of proximal, unidentified, sulfides, or H₂S associated with deep source beds. Jarosite is highly soluble, and its presence suggests that abundant fluid flow has not occurred in this region since its formation. This terminal cement‐forming event must have occurred prior to sandstone exhumation and erosion to form the current extreme landscape at Mollies. This site exhibits the influence that fluid geochemistry, sedimentary mineralogy, and structural fabric have on geomorphic evolution.     

Chronicles of vadose zone diagenesis: cone‐shaped iron oxide concretions,Triassic Trujillo Formation,Palo Duro Canyon,Texas

Unusual cone‐shaped iron oxide concretions occur in the Late Triassic, lower fluvial sandstone member of the Trujillo Formation at Palo Duro Canyon in the Texas panhandle. In situ concretions are significant because they record both historical information about past processes that occurred within the geologic unit and present‐day information about the ability of the unit to conduct fluids. The dominant orientation of the concretions is cone‐apex up, body radiating down and out, with long axis perpendicular to bedding. Concretion morphologies are associated with the sedimentary texture and primary bedding structure of the host rock and the corresponding hydrologic regime (i.e. advection versus dispersion for iron‐transport behavior). Three lithofacies in the lower Trujillo member exhibit different cone forms. Field observations of cone orientation and morphology suggest vadose conditions for diagenetic precipitation of iron oxide cements, with timing potentially represented by the major pre‐Miocene unconformity.     

Civil War Iron and the H.L. Hunley Iron Ballast

At the beginning of the American Civil War in 1861, the Union greatly outpaced the Confederacy in industrial manufacturing capabilities. The Confederacy's economy prior to the conflict was largely based on agriculture, and the Southern states lacked the facilities and skilled labourers to produce iron on the scale necessary to compete with the Union. The possibility of importing products was greatly diminished when President Lincoln instituted a naval blockade around major Southern ports, limiting the amount of cargo that could be imported from Europe. Consequently, the Confederacy was forced to adapt ironworks to wartime purposes. Despite these adaptations, the Confederacy suffered from iron shortages throughout the war. This paper uses the iron ballast found on the Confederate submarine H.L. Hunley as a case study for the manufacturing processes, labour relationships and social significance of iron production and usage in the Confederacy.     

SCIENTIFIC ANALYSIS OF SEVENTH‐CENTURY GLASS FRAGMENTS FROM THE CRYPTA BALBI IN ROME*

Inductively coupled plasma emission spectroscopy, reflectance spectroscopy and X‐ray diffraction were used to study seventh‐century AD glass fragments from the Crypta Balbi in Rome. All the samples were found to be silica‐soda‐lime glasses. Iron determines the colour of blue‐green, green and yellow‐green transparent glasses; chemical composition suggests deliberate addition of iron and/or manganese in about half the samples. Copper was found as the main colourant in red, pale blue and blue‐green opaque fragments; elemental copper acts as an opacifier in red glass, and calcium antimonate in white, pale blue and blue‐green glasses. Detection of antimony in transparent fragments suggests recycling of opaque mosaic tesserae.     

THE BLUE ENAMELS IN THE BAROQUE DECORATIONS OF THE CHURCHES OF PALERMO,SICILY: FE2+‐COLOURED GLASSES FROM LIME KILNS*

Deep blue glasses coloured by octahedral Fe²⁺ cations are often reported as textbook examples of blue pigmentation. However, despite the possibility of laboratory synthesis under reducing conditions, to date there are no well‐reported occurrences of their production and use in the past. A thorough historical, ethnographic, mineralogical, and chemico‐physical investigation of the ‘smaltini di calcara’ from several baroque churches in Palermo, Sicily, has revealed that the blue enamels widely used for altar decorations in the 17th and 18th centuries are actually a unique case of ancient blue glasses pigmented by divalent iron cations in distorted octahedral coordination. This mixed‐alkali glass was accidentally produced under severely reducing conditions in the local kilns during production of lime.     

Implications of Reappraising the Iron‐Deficiency Anemia Hypothesis

In 2009, Walker and colleagues questioned the validity of the iron‐deficiency anemia hypothesis as an explanatory mechanism for the presence of porotic hyperostosis (PH) and cribra orbitalia. They presented evidence demonstrating that iron deficiency inhibits, rather than promotes, marrow hypertrophy and argued a link between both PH and hemolytic or megaloblasic anemias (including vitamin B₁₂ deficiency). This paper suggests that dismissing the iron‐deficiency anemia hypothesis may be premature, but, if dismissed, may result in unforeseen consequences. Vitamin B₁₂ deficiency and iron deficiency often result from similar proximate causes, i.e. lack of animal protein in the diet and sanitation problems that lead to parasitic or diarrheal diseases, thereby promoting nutrient losses. As a result, vitamin B₁₂ deficiency and iron deficiency commonly co‐occur. In individuals with a co‐occurrence of iron deficiency and vitamin B₁₂ deficiency, a possible inhibition of marrow hypertrophy caused by iron deficiency may prevent the development of PH, despite the presence of (vitamin B₁₂) nutritional deficiency. The implications of dismissing the iron‐deficiency anemia hypothesis are that many skeletal populations may exhibit hidden heterogeneity, i.e. individuals who are the most nutritionally stressed, with multiple nutrient deficiencies, would mimic the non‐stressed individuals and neither would show evidence of PH. However, the inclusion of multiple stress indicators and greater understanding of biocultural context in bioarchaeological analyses may mitigate the potential impacts of hidden heterogeneity in the expression of PH. Copyright © 2013 John Wiley & Sons, Ltd.     

Monitoring fluid chemistry in iron oxide–copper–gold‐related metasomatic processes,eastern Mt Isa Block,Australia

Most researchers in the Proterozoic eastern Mt Isa Block, NW Queensland, Australia, favour magmatic fluid and salt sources for sodic‐(calcic) alteration and iron oxide–copper–gold mineralization. Here we compare spatial, mineralogic and stable isotope data from regional alteration assemblages with magmatic and magmatic‐hydrothermal interface rocks in order to track chemical and isotopic variations in fluid composition away from inferred fluid sources. Tightly clustered δ¹⁸O values for magnetite, quartz, feldspar and actinolite for igneous‐hosted samples reflect high temperature equilibration in the magmatic‐hydrothermal environment. In contrast, these minerals record predominantly higher δ¹⁸O values in regional alteration and Cu–Au mineralization. This dichotomy reflects partial equilibration with isotopically heavier wallrocks and slightly lower temperatures. Increases in Si concentrations of metasomatic amphiboles relative to igneous amphiboles in part reflect cooling of metasomatic fluids away from igneous rocks. Variations in X_Mg for metasomatic amphiboles indicate local wallrock controls on amphibole chemistry, while variations in X_Cl/X_OH ratios for amphiboles (at constant X_Mg) indicate variable aH₂O/aHCl ratios for metasomatic fluids. Biotite geochemistry also reflects cooling and both increases and decreases in aH₂O/aHCl for fluids away from plutonic rocks. Decreased aH₂O/aHCl ratios for metasomatic fluids reflect in part scavenging of chlorine out of meta‐evaporite sequences, although this process requires already saline fluids. Local increases in aH₂O/aHCl ratios, as well as local decreases in δ¹⁸O values for some minerals (most notably haematite and epithermal‐textured quartz), may indicate ingress of low salinity, low δ¹⁸O fluids of possible meteoric origin late in the hydrothermal history of the region. Taken together, our observations are most consistent with predominantly magmatic sources for metasomatic fluids in the eastern Mt Isa Block, but record chemical and isotopic variations along fluid flow paths that may be important in explaining some of the diversity in alteration and mineralization styles in the district.     

Charcoal analysis of industrial fuelwood from medieval and early modern iron-working sites in Bilsdale and Rievaulx,North Yorkshire,UK: evidence for species selection and woodland management

Abstract

This paper presents the results of species diversity and dendrological analyses of archaeological charcoal excavated from medieval and early modern iron production sites in Bilsdale, and at Rievaulx in the neighbouring valley of Ryedale, North Yorkshire, UK. Standard methods of quantification are used to assess species diversity, sampling sufficiency and taxa presence. The assessment of dendrological features provides additional evidence for growth trends and cutting cycles analogous with cyclical woodland management, as well as environmental and growing conditions. Analysis of archaeological charcoal from four medieval bloomery furnace sites in Bilsdale, and from the site of the hammersmithy and blast furnace at the early modern iron works at Rievaulx, provide comparable data-sets which indicate a change in cutting practise and dominant species selection for industrial fuelwood occurred between the 12th- and mid-16th centuries AD. Results show that dominant species presence changed from an admixture of predominantly birch (Betula sp.) and hazel (Corylus avellana) sourced from small calibre branchwood and stemwood used in the medieval bloomery furnaces, to a dominant oak (Quercus sp.) presence from standard sources used at the Rievaulx iron works by the mid-16th century. Whilst it is uncertain whether this change in dominant species composition and the source of industrial fuelwood is related to changes in local availability, or the result of the technological transition to blast furnace processing which occurred at this time, estate records reveal a woodland management campaign was instigated to supply and maintain fuelwood supplies to the iron works at Rievaulx which coincides with the introduction of Tudor arboricultural legislation in the 1540s.     

The “Iron Cage” and the “Shell as Hard as Steel”: Parsons,Weber, and the Stahlhartes Gehäuse Metaphor in the Protestant Ethic and the Spirit of Capitalism

In the climax to The Protestant Ethic, Max Weber writes of the stahlhartes Gehäuse that modern capitalism has created, a concept that Talcott Parsons famously rendered as the “iron cage.” This article examines the status of Parsons's canonical translation; the putative sources of its imagery (in Bunyan's Pilgrim's Progress); and the more complex idea that Weber himself sought to evoke with the “shell as hard as steel”: a reconstitution of the human subject under bureaucratic capitalism in which “steel” becomes emblematic of modernity. Steel, unlike the “element” iron, is a product of human fabrication. It is both hard and potentially flexible. Further, whereas a cage confines human agents, but leaves their powers otherwise intact, a “shell” suggests that modern capitalism has created a new kind of being. After examining objections to this interpretation, I argue that whatever the problems with Parsons's “iron cage” as a rendition of Weber's own metaphor, it has become a “traveling idea,” a fertile coinagein its own right, an intriguing example of how the translator's imagination can impose itself influentially on the text and its readers.     

COINS,ARTEFACTS AND ISOTOPES—ARCHAEOMETALLURGY AND ARCHAEOMETRY*

Archaeometallurgy is one of the earliest manifestations of archaeometric research, using science‐based approaches to address cultural–historical questions. This review first outlines the extent of the field, defining in some detail the main branches of archaeometallurgy, and their specific methodological approaches. It then looks at some of the early publications pioneering archaeometallurgical research, to set the scene for the publication pattern of archaeometallurgy in general, and the role that Archaeometry played in publishing archaeometallurgical research. The analysis of archaeometallurgy‐themed publications in Archaeometry, their change over time and their relationship to the total range of work done in the field indicates that there is a rather narrowly defined and specific type of archaeometallurgy that gets published in Archaeometry, initially with a strong focus on coin and object analysis, often combined with method developments. The more recent developments in isotope‐based studies in archaeometallurgy find only a limited representation in the journal, despite the leading role that the Isotrace Laboratory played in this discipline, for some considerable length of time. More recently, this Archaeometry‐specific ‘flavour’ of archaeometallurgy seems to weaken, with an increase of papers on iron and on primary production in general, subjects still much under‐represented.