Nathaniel L Erb-Satullo | Cranfield University (original) (raw)

Papers by Nathaniel L Erb-Satullo

Journal of Archaeological Science: Reports, 2023

Obsidian sourcing studies have a long history in the Near East, but relatively few have focused o... more Obsidian sourcing studies have a long history in the Near East, but relatively few have focused on obsidian exchange after the Early Bronze Age. Here, we present a multi-technique analysis of an assemblage of 111 obsidian artifacts from excavated Late Bronze and Early Iron Age (LBA-EIA; c. 15th-6th c BCE) contexts at Mtsvane Gora, southern Georgia. Because the site is situated in the lowland Kura Valley and the nearest obsidian sources are in the highlands to the south and west, obsidian provenance can serve as a proxy for mapping highland-lowland interactions. Chemical compositions analyzed via portable X-ray fluorescence spectrometry (pXRF), electron microprobe analysis (EMPA), and laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS), were compared with existing geological datasets of chemical analyses to identify the source of all but one of the artifacts analyzed. The results show that Chikiani, a source in the highlands of southern Georgia, was the geological origin of >90% of the objects analyzed. While acknowledging that obsidian exchange is just one aspect of highland-lowland interaction, this finding implies that Mtsvane Gora’s connections with the adjacent highlands were skewed towards greater engagement with some highland areas relative to others. More generally, the research suggests that geographic adjacency of highlands and lowlands does not necessarily mean that they were highly interconnected.

Journal of Archaeological Science, 2015

The South Caucasus was a major center of metal production in the Late Bronze and Early Iron Ages.... more The South Caucasus was a major center of metal production in the Late Bronze and Early Iron Ages. Nowhere is this more clear than in the hills and mountains in the southeastern Black Sea region (ancient Colchis), where exceptionally large numbers of metal production sites have been found. Chemical and microscopic analysis of slagged technical ceramics at these sites illuminates several aspects of both raw copper and tin bronze alloy production. Copper ores were smelted in a complex multi-stage process designed to extract metal from sulfide ores. Technical ceramics served as containers for a range of different reactions, from the first phase of smelting, in which the copper sulfides were likely consolidated into a matte, though later stages of matte

Current World Archaeology, 2022

Issue 112 CurrentWorldArChAeology LEFT A depiction of Jason and the Golden Fleece on a 4th-centur... more Issue 112 CurrentWorldArChAeology LEFT A depiction of Jason and the Golden Fleece on a 4th-century BC vessel from south Italy. The myth of Jason and the Argonauts was celebrated by the Greeks and the Romans. It is attested as early as the 8th century BC, but one of the most substantial surviving versions, the Argonautica by Apollonius of Rhodes, dates to the 3rd century BC. How does the legendary wealth of Jason's destination, Colchis, compare to archaeological finds from the region? OPPOSITE TOP Map of the Caucasus showing ore deposits and sites with gold dating to 4000-500 BC. BOTTOM Gold deposits in the mountains of the western Caucasus (including Svaneti, the region pictured here) may have been the source of gold for the artefacts found in the adjacent Colchis lowlands. The Golden Fleece paradox Why did gold disappear for centuries from ancient societies in the Caucasus? The Caucasus were home to some of the world's earliest and most proficient goldsmiths. Despite an association between this metal and the mountains that became so strong it was woven into mythology, gold artefacts more or less disappear from a large part of the region for a period of some seven centuries. Nathaniel Erb-Satullo investigates why.

Journal of Field Archaeology, 2022

Fortresses are defining features of the Late Bronze and Early Iron Age landscape in the South Cau... more Fortresses are defining features of the Late Bronze and Early Iron Age landscape in the South Caucasus, with hundreds of sites recorded in archaeological surveys in Georgia, Armenia and Azerbaijan, and northeastern Turkey. Yet, research on how these communities functioned is dominated by evidence from the small fraction of these sites that have been excavated, and regional variability remains underexplored. This paper discusses excavations at two such fortresses in the Lesser Caucasus borderlands and contextualizes them within global discussions about fortresses and their associated communities. Analysis of architecture, ceramics, and small finds identified evidence for a diverse range of activities within these compounds, including both craft production and ritual activity. While the size and construction of the two fortresses differ, the evidence for significant occupation at both suggests that these fortresses were durable communities, not temporary refugia. Further work is necessary, however, to assess whether these fortresses were highly ordered institutions centralized under elite rule or heterarchical communities joined by common interest.

Cambridge Archaeological Journal, 2022

Discussions of spatial relationships are persistent features of research on the organization of c... more Discussions of spatial relationships are persistent features of research on the organization of craft production. Despite the centrality of spatial issues, the correspondence between spatial patterning and economic organization remains relatively under-theorized, especially around questions of power and control. Drawing from the literature on craft ecology, specialization and landscape archaeology, I develop an approach that considers spatial scales of patterning, the power projection of elites and institutions and the articulation between elements of the crafting landscape. This approach recognizes the complex sets of factors affecting spatial patterning and ultimately produces a more robust understanding of how ancient economic systems were organized. These ideas are explored through a case study on Late Bronze and Early Iron Age metal production in the Caucasus, clarifying the organizational logics of the metal economy and highlighting how this industry differed in significant ways from other contemporary metal-producing regions in the ancient Near East.

The work describes archaeological finds unearthed and studied during a 4 year joint Georgian and ... more The work describes archaeological finds unearthed and studied during a 4 year joint Georgian and British expedition (2010-2012) on the territory of southwestern Georgia. The study of early ironware is admitted to be among the most challenging areas of historical sciences. Broad scholarly interest in it is associated with the significant role of iron in early communities. The early use of iron has been confirmed in many advanced states of the Ancient East, but iron mining and processing (early groups of iron smelting workshops) has not so far been attested in these areas – at least to the extent to meet the local demand. The situation is different on the territory of western Georgia (historical Colchis), where Georgian specialists have discovered and studied a significant number of large-scale mining and metallurgical centers in the last 60 years. Recent findings add more evidence to the opinion that the eastern and south-eastern Black Sea area (historical Colchis) was the importa...

Scientific Reports, 2021

In research on early invention and innovation, technological “firsts” receive enormous attention,... more In research on early invention and innovation, technological “firsts” receive enormous attention, but technological “lasts”—instances of abandonment and rejection—are arguably more informative about human technological behavior. Yet, cases of technological discontinuance are largely ignored in studies of early innovation, as the lack of robust datasets makes identification and analysis difficult. A large-scale geospatial analysis of more than 4500 gold objects from the Caucasus, an early center of gold innovation, shows a precipitous decline at 1500 BC in precisely the places with the earliest global evidence of gold mining (c. 3000 BC). Testing various causal models reveals that social factors, rather than resource limitations or demographic disruption, were the primary causes of this rejection. These results indicate that prior models of technological rejection and loss have underestimated the range of conditions in which they can occur, and provide empirical support for theories of innovation that reject notions about the linearity of technological progress.

Archaeometry, 2021

Recent research has brought the prolific bronze industry of Bronze Age Colchis (modern western Ge... more Recent research has brought the prolific bronze industry of Bronze Age Colchis (modern western Georgia) into focus, but many aspects are still poorly understood. This study synthesizes and reinterprets legacy Cu alloy compositional data to investigate technological choices and spatial patterning. It reveals a massive injection of fresh copper into the system during the Late Bronze-Early Iron Age, and a high degree of selectivity in the alloys used for different objects, with colour being as important as hardness in determining these choices. Spatial analyses show significant geographical variability in alloying practices, which map onto topo-graphical zones in unexpected ways. We also explore recycling practices and argue that the term encompasses a range of different reuse activities, which may be employed under differing economic conditions. Finally, the data suggest relatively extensive primary alloying of tin and copper in the Late Bronze and Early Iron Ages, which further substantiates the speculation that some local tin sources were exploited.

Advances in Archaeomaterials, 2020

The field of archaeomaterials research has enormous potential to shed light on past innovation pr... more The field of archaeomaterials research has enormous potential to shed light on past innovation processes. However , this potential has been only partially recognized outside its immediate practitioners, despite the fact that innovation and technology change are topics of enduring interest in archaeology and the broader social sciences. This review explores the relationship between archaeomaterials research and the interdisciplinary study of innovation, and maps out a path toward greater integration of materials analysis into these discussions. To foster this integration, this review has three aims. First, I sketch the theoretical landscape of approaches to the study of innovation in archaeology and neighboring disciplines. I trace how theoretical traditions like evolutionary archaeology have influenced archaeomaterials approaches to questions of technological change while also highlighting cases where work by archaeomaterials researchers anticipated trends in the anthropology of technology. Next, I distill a series of core concerns that crosscut these different theoretical perspectives. Finally, I describe examples where archaeomaterials research has deepened scholarly understanding of innovation processes and addressed these core questions. The future of archaeomaterials research lies in engagement with these broader discussions and effective communication of the contributions that materials analysis can make to building a comparative understanding of innovation processes.

Journal of Archaeological Science, 2020

Models for iron innovation in Eurasia are predicated on understanding the relationship between th... more Models for iron innovation in Eurasia are predicated on understanding the relationship between the bronze and iron industries. In eastern Anatolia, the South Caucasus, and Iran, the absence of scientific analyses of metal-lurgical debris has obscured the relative chronology, spatial organization, and economic context of early iron and contemporary copper-alloy industries. Survey and excavation at Mtsvane Gora, a fortified hilltop site close to major polymetallic ore sources in the Lesser Caucasus range, recovered metallurgical debris dating to the 8th-6th centuries BC. Optical microscopy, scanning electron microscopy, and energy and wavelength dispersive spec-trometry revealed evidence for both iron and copper-alloy metallurgy, including smithing and alloying. Metal particles trapped within clear iron smithing slags were contaminated with copper, arsenic, and tin, suggesting that iron and copper-alloy working took place in the same hearths. The discovery of a small fragment of un-processed material consisting of pyrite and jarosite, minerals typical of major nearby polymetallic ore deposits, links the secondary smithing and alloying at Mtsvane Gora with nearby mining activities, though the nature of those connections remains unclear. While the earliest iron in the region probably predates the Mtsvane Gora assemblage, the remains date to a period when iron use was still expanding, and they are at present the earliest analytically confirmed, radiocarbon-dated iron metallurgical debris in the Caucasus. The remains are therefore significant for understanding the spread of iron innovation eastward from Anatolia and the Levant. When considered in light of evidence from other Near Eastern sites, the results support a model for innovation in which early iron manufacturing was at least partially integrated with the copper-alloy metallurgical economy.

Antiquity, 2020

The southeastern Black Sea area is a key region for understanding the history of iron metallurgy.... more The southeastern Black Sea area is a key region for understanding the history of iron metallurgy. While Classical texts mention the people living in this area as producers, and perhaps even inventors, of iron, material evidence has been lacking. Recent archaeological survey and scientific analyses now make it possible to investigate iron technologies in the region during the mid to late first millennium BC and the medieval period, providing new insights into the metallurgical tradition that inspired such admiration in the Graeco-Roman world. These results have implications for the smelting of iron in liquid state, although it remains unclear where and when this technology first appeared in Western Eurasia.

Antiquity, 2019

The South Caucasus has been largely absent in broader discussions of prehistoric population aggre... more The South Caucasus has been largely absent in broader discussions of prehistoric population aggregation in Greater Eurasia. The authors use remote sensing, surface collection and mag-netometry to investigate two hilltop fortress settlements at the margins of the Kura River Basin, with a particular emphasis on satellite settlements around the main hills. The results support a model of settlement growth in which previously mobile groups settled around the fortress, while maintaining a degree of spatial and social separation. The use of multiple survey techniques reveals a complex picture of settlement organisation, with implications for comparative analysis of prehistoric population aggregation models.

Journal of Archaeological Research, 2019

This review synthesizes field research, textual analysis, and archaeometric data to evaluate diff... more This review synthesizes field research, textual analysis, and archaeometric data to evaluate different explanations for the spread of iron in the ancient Near East. Current evidence supports an Anatolian origin for extractive iron metallurgy on a limited scale sometime in the early 2nd millennium BC. However, the first major expansion of iron, both in Anatolia and across the wider Near East, occurred in the late second and early first millennium BC. Explanations that place iron adoption within its broader social context are favored over those that consider material or geological properties in isolation. A recurring theme is the importance of comparative analysis, both geographically and between the iron and bronze economies, to explore how social, political, and economic conditions affected adoption patterns.

Radiocarbon, 2018

The Eastern Black Sea region of the South Caucasus contains an extremely rich record of metallurg... more The Eastern Black Sea region of the South Caucasus contains an extremely rich record of metallurgical remains that is poorly known outside of the former Soviet Union. Large numbers of relatively small smelting sites dot the foothill regions, forming a dispersed, yet large-scale metallurgical landscape. New fieldwork in the region has followed up on earlier Soviet period research, relocating and reanalyzing previously known sites and identifying new ones. This paper presents a series of 33 radiocarbon (14C) dates from copper and iron smelting sites in this region. Dates from copper smelting sites suggest that copper smelting occurred over a shorter and more intense period than previously thought, between about 1300 and 800 BC. Dates from newly discovered iron smelting sites place these activities in two episodes during the Classical-Hellenistic period (ca. 500–200 BC) and the High Medieval period
(ca. AD 1050–1400). The dramatic expansion in bronze production immediately prior to the adoption of iron mirrors patterns in other regions of Europe and the Near East, and has implications for understanding the economic contexts in which iron emerged. While the new dates from iron smelting sites provide only an initial outline of the iron production chronology in the region, they represent an important step for resolving outstanding issues from previous investigations.

Despite the large numbers of ancient mining and metal production sites in the South Caucasus, spa... more Despite the large numbers of ancient mining and metal production sites in the South Caucasus, spatial analyses of metal production landscapes are far from common. Archaeological survey in the ore-rich foothills of Kvemo Kartli, southern Georgia, demonstrates the potential for integrating previous geological and archaeological research into present-day landscape archaeology projects. Combining reports of earlier excavations, satellite imagery and ground-level observations, 15 hilltop sites and 9 sites with possible mining activity were mapped. Systematic surface collection revealed that most of these hilltop sites contain at least some traces of Late Bronze–Early Iron Age (LBA–EIA, c. 1500–600 BC) habitation, with a number of sites having a predominantly LBA–EIA ceramic assemblage. The relative positioning of hilltop settlement and mining sites shows that settlement sites were frequently positioned in ways that controlled access to ore deposits. Metallurgical activity, evidenced by the presence of slag, was attested at several of these hilltop sites. In one or two cases, settlements were built directly adjacent to ore deposits. However, it remains an open question whether proximity to ore deposits and evidence of metal production at these sites meant that metal production was administered or managed by elites within those communities. Detailed investigation of the spatial contexts of metal production at all spatial scales is necessary for understanding the factors driving social and technological change during this period.

Studies of metal production frequently show a correlation between scale and organizational comple... more Studies of metal production frequently show a correlation between scale and organizational complexity.
The remarkably rich landscapes of metal-producing sites of late 2nd-early 1st millennium BC Colchis provide
an unprecedented opportunity to reexamine this apparent correlation. Investigations of copper
smelting sites show that industries with a large aggregate output can be the result of numerous small
groups of metalworkers acting independently. Spatial data on site distributions, estimates of productive
output, and archaeometric data on ore procurement patterns were integrated to reconstruct the organization
of production. Judicious use of a portable X-ray fluorescence spectrometer (pXRF) showed that not
only were smelting sites highly dispersed, but also that metalworkers at different sites were using ores
from geologically distinct deposits. This innovative approach helped to reconstruct the organization of
production in a distinctive metal production landscape, bridging an enduring divide between
landscape-scale and microscopic investigations of craft production.

A B S T R A C T Understanding the spatial distribution of different craft production activities i... more A B S T R A C T Understanding the spatial distribution of different craft production activities is an essential part of any investigation into the organization of production. In the Iron Age southern Levant, discussions of the rise of iron often revolve around the relative organization of bronze and iron production. For these reasons, identifying where different stages of metal production occurred is essential for testing models of technological change during this period. This study reviews the challenges of identifying different stages of metal production from often-ephemeral residues found at settlement sites, with particular emphasis on the question of urban iron smelting in the early Iron Age southern Levant. These considerations are applied to the analysis of a small but significant assemblage of metal production remains from Iron IIB Ashkelon (c. 8th century BCE), using macroscopic observations, chemical analysis, and microscopy. The results of these analyses support the conclusion that multiple iron production processes—likely including both smelting and smithing—took place in or near a domestic quarter at Ashkelon. With one or two exceptions, copper production residues are restricted to secondary refining and casting residues. Copper smelting was carried out elsewhere. If this pattern holds as more urban production debris is recognized and analyzed, such differences in the relative organization of iron and copper-alloy production may provide clues as to why iron production expanded dramatically in the early 1st millennium BCE.

The South Caucasus was a major center of metal production in the Late Bronze and Early Iron Ages.... more The South Caucasus was a major center of metal production in the Late Bronze and Early Iron Ages. Nowhere is this more clear than in the hills and mountains in the southeastern Black Sea region (ancient Colchis), where exceptionally large numbers of metal production sites have been found. Chemical and microscopic analysis of slagged technical ceramics at these sites illuminates several aspects of both raw copper and tin bronze alloy production. Copper ores were smelted in a complex multi-stage process designed to extract metal from sulfide ores. Technical ceramics served as containers for a range of different reactions, from the first phase of smelting, in which the copper sulfides were likely consolidated into a matte, though later stages of matte processing and metal copper production in smaller crucibles. In addition, a single crucible fragment, recovered from a late 2nd millennium BC slag heap, demonstrates that tin bronze was created by the direct addition of cassiterite tin ore, probably of alluvial origin, to metallic copper. The crucible's context, the use of cassiterite ore rather than tin metal, and a review of local geology suggests that the tin used in this crucible came from nearby, with the most likely source being the Vakijvari and Bzhuzhi gorges roughly 10-15 km away. While a single fragment does not speak to the regularity of this practice, at the very least it raises the possibility that the Colchian bronze industry was based on local rather than imported tin.

Journal of Archaeological Science: Reports, 2023

Obsidian sourcing studies have a long history in the Near East, but relatively few have focused o... more Obsidian sourcing studies have a long history in the Near East, but relatively few have focused on obsidian exchange after the Early Bronze Age. Here, we present a multi-technique analysis of an assemblage of 111 obsidian artifacts from excavated Late Bronze and Early Iron Age (LBA-EIA; c. 15th-6th c BCE) contexts at Mtsvane Gora, southern Georgia. Because the site is situated in the lowland Kura Valley and the nearest obsidian sources are in the highlands to the south and west, obsidian provenance can serve as a proxy for mapping highland-lowland interactions. Chemical compositions analyzed via portable X-ray fluorescence spectrometry (pXRF), electron microprobe analysis (EMPA), and laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS), were compared with existing geological datasets of chemical analyses to identify the source of all but one of the artifacts analyzed. The results show that Chikiani, a source in the highlands of southern Georgia, was the geological origin of >90% of the objects analyzed. While acknowledging that obsidian exchange is just one aspect of highland-lowland interaction, this finding implies that Mtsvane Gora’s connections with the adjacent highlands were skewed towards greater engagement with some highland areas relative to others. More generally, the research suggests that geographic adjacency of highlands and lowlands does not necessarily mean that they were highly interconnected.

Journal of Archaeological Science, 2015

The South Caucasus was a major center of metal production in the Late Bronze and Early Iron Ages.... more The South Caucasus was a major center of metal production in the Late Bronze and Early Iron Ages. Nowhere is this more clear than in the hills and mountains in the southeastern Black Sea region (ancient Colchis), where exceptionally large numbers of metal production sites have been found. Chemical and microscopic analysis of slagged technical ceramics at these sites illuminates several aspects of both raw copper and tin bronze alloy production. Copper ores were smelted in a complex multi-stage process designed to extract metal from sulfide ores. Technical ceramics served as containers for a range of different reactions, from the first phase of smelting, in which the copper sulfides were likely consolidated into a matte, though later stages of matte

Current World Archaeology, 2022

Issue 112 CurrentWorldArChAeology LEFT A depiction of Jason and the Golden Fleece on a 4th-centur... more Issue 112 CurrentWorldArChAeology LEFT A depiction of Jason and the Golden Fleece on a 4th-century BC vessel from south Italy. The myth of Jason and the Argonauts was celebrated by the Greeks and the Romans. It is attested as early as the 8th century BC, but one of the most substantial surviving versions, the Argonautica by Apollonius of Rhodes, dates to the 3rd century BC. How does the legendary wealth of Jason's destination, Colchis, compare to archaeological finds from the region? OPPOSITE TOP Map of the Caucasus showing ore deposits and sites with gold dating to 4000-500 BC. BOTTOM Gold deposits in the mountains of the western Caucasus (including Svaneti, the region pictured here) may have been the source of gold for the artefacts found in the adjacent Colchis lowlands. The Golden Fleece paradox Why did gold disappear for centuries from ancient societies in the Caucasus? The Caucasus were home to some of the world's earliest and most proficient goldsmiths. Despite an association between this metal and the mountains that became so strong it was woven into mythology, gold artefacts more or less disappear from a large part of the region for a period of some seven centuries. Nathaniel Erb-Satullo investigates why.

Journal of Field Archaeology, 2022

Fortresses are defining features of the Late Bronze and Early Iron Age landscape in the South Cau... more Fortresses are defining features of the Late Bronze and Early Iron Age landscape in the South Caucasus, with hundreds of sites recorded in archaeological surveys in Georgia, Armenia and Azerbaijan, and northeastern Turkey. Yet, research on how these communities functioned is dominated by evidence from the small fraction of these sites that have been excavated, and regional variability remains underexplored. This paper discusses excavations at two such fortresses in the Lesser Caucasus borderlands and contextualizes them within global discussions about fortresses and their associated communities. Analysis of architecture, ceramics, and small finds identified evidence for a diverse range of activities within these compounds, including both craft production and ritual activity. While the size and construction of the two fortresses differ, the evidence for significant occupation at both suggests that these fortresses were durable communities, not temporary refugia. Further work is necessary, however, to assess whether these fortresses were highly ordered institutions centralized under elite rule or heterarchical communities joined by common interest.

Cambridge Archaeological Journal, 2022

Discussions of spatial relationships are persistent features of research on the organization of c... more Discussions of spatial relationships are persistent features of research on the organization of craft production. Despite the centrality of spatial issues, the correspondence between spatial patterning and economic organization remains relatively under-theorized, especially around questions of power and control. Drawing from the literature on craft ecology, specialization and landscape archaeology, I develop an approach that considers spatial scales of patterning, the power projection of elites and institutions and the articulation between elements of the crafting landscape. This approach recognizes the complex sets of factors affecting spatial patterning and ultimately produces a more robust understanding of how ancient economic systems were organized. These ideas are explored through a case study on Late Bronze and Early Iron Age metal production in the Caucasus, clarifying the organizational logics of the metal economy and highlighting how this industry differed in significant ways from other contemporary metal-producing regions in the ancient Near East.

The work describes archaeological finds unearthed and studied during a 4 year joint Georgian and ... more The work describes archaeological finds unearthed and studied during a 4 year joint Georgian and British expedition (2010-2012) on the territory of southwestern Georgia. The study of early ironware is admitted to be among the most challenging areas of historical sciences. Broad scholarly interest in it is associated with the significant role of iron in early communities. The early use of iron has been confirmed in many advanced states of the Ancient East, but iron mining and processing (early groups of iron smelting workshops) has not so far been attested in these areas – at least to the extent to meet the local demand. The situation is different on the territory of western Georgia (historical Colchis), where Georgian specialists have discovered and studied a significant number of large-scale mining and metallurgical centers in the last 60 years. Recent findings add more evidence to the opinion that the eastern and south-eastern Black Sea area (historical Colchis) was the importa...

Scientific Reports, 2021

In research on early invention and innovation, technological “firsts” receive enormous attention,... more In research on early invention and innovation, technological “firsts” receive enormous attention, but technological “lasts”—instances of abandonment and rejection—are arguably more informative about human technological behavior. Yet, cases of technological discontinuance are largely ignored in studies of early innovation, as the lack of robust datasets makes identification and analysis difficult. A large-scale geospatial analysis of more than 4500 gold objects from the Caucasus, an early center of gold innovation, shows a precipitous decline at 1500 BC in precisely the places with the earliest global evidence of gold mining (c. 3000 BC). Testing various causal models reveals that social factors, rather than resource limitations or demographic disruption, were the primary causes of this rejection. These results indicate that prior models of technological rejection and loss have underestimated the range of conditions in which they can occur, and provide empirical support for theories of innovation that reject notions about the linearity of technological progress.

Archaeometry, 2021

Recent research has brought the prolific bronze industry of Bronze Age Colchis (modern western Ge... more Recent research has brought the prolific bronze industry of Bronze Age Colchis (modern western Georgia) into focus, but many aspects are still poorly understood. This study synthesizes and reinterprets legacy Cu alloy compositional data to investigate technological choices and spatial patterning. It reveals a massive injection of fresh copper into the system during the Late Bronze-Early Iron Age, and a high degree of selectivity in the alloys used for different objects, with colour being as important as hardness in determining these choices. Spatial analyses show significant geographical variability in alloying practices, which map onto topo-graphical zones in unexpected ways. We also explore recycling practices and argue that the term encompasses a range of different reuse activities, which may be employed under differing economic conditions. Finally, the data suggest relatively extensive primary alloying of tin and copper in the Late Bronze and Early Iron Ages, which further substantiates the speculation that some local tin sources were exploited.

Advances in Archaeomaterials, 2020

The field of archaeomaterials research has enormous potential to shed light on past innovation pr... more The field of archaeomaterials research has enormous potential to shed light on past innovation processes. However , this potential has been only partially recognized outside its immediate practitioners, despite the fact that innovation and technology change are topics of enduring interest in archaeology and the broader social sciences. This review explores the relationship between archaeomaterials research and the interdisciplinary study of innovation, and maps out a path toward greater integration of materials analysis into these discussions. To foster this integration, this review has three aims. First, I sketch the theoretical landscape of approaches to the study of innovation in archaeology and neighboring disciplines. I trace how theoretical traditions like evolutionary archaeology have influenced archaeomaterials approaches to questions of technological change while also highlighting cases where work by archaeomaterials researchers anticipated trends in the anthropology of technology. Next, I distill a series of core concerns that crosscut these different theoretical perspectives. Finally, I describe examples where archaeomaterials research has deepened scholarly understanding of innovation processes and addressed these core questions. The future of archaeomaterials research lies in engagement with these broader discussions and effective communication of the contributions that materials analysis can make to building a comparative understanding of innovation processes.

Journal of Archaeological Science, 2020

Models for iron innovation in Eurasia are predicated on understanding the relationship between th... more Models for iron innovation in Eurasia are predicated on understanding the relationship between the bronze and iron industries. In eastern Anatolia, the South Caucasus, and Iran, the absence of scientific analyses of metal-lurgical debris has obscured the relative chronology, spatial organization, and economic context of early iron and contemporary copper-alloy industries. Survey and excavation at Mtsvane Gora, a fortified hilltop site close to major polymetallic ore sources in the Lesser Caucasus range, recovered metallurgical debris dating to the 8th-6th centuries BC. Optical microscopy, scanning electron microscopy, and energy and wavelength dispersive spec-trometry revealed evidence for both iron and copper-alloy metallurgy, including smithing and alloying. Metal particles trapped within clear iron smithing slags were contaminated with copper, arsenic, and tin, suggesting that iron and copper-alloy working took place in the same hearths. The discovery of a small fragment of un-processed material consisting of pyrite and jarosite, minerals typical of major nearby polymetallic ore deposits, links the secondary smithing and alloying at Mtsvane Gora with nearby mining activities, though the nature of those connections remains unclear. While the earliest iron in the region probably predates the Mtsvane Gora assemblage, the remains date to a period when iron use was still expanding, and they are at present the earliest analytically confirmed, radiocarbon-dated iron metallurgical debris in the Caucasus. The remains are therefore significant for understanding the spread of iron innovation eastward from Anatolia and the Levant. When considered in light of evidence from other Near Eastern sites, the results support a model for innovation in which early iron manufacturing was at least partially integrated with the copper-alloy metallurgical economy.

Antiquity, 2020

The southeastern Black Sea area is a key region for understanding the history of iron metallurgy.... more The southeastern Black Sea area is a key region for understanding the history of iron metallurgy. While Classical texts mention the people living in this area as producers, and perhaps even inventors, of iron, material evidence has been lacking. Recent archaeological survey and scientific analyses now make it possible to investigate iron technologies in the region during the mid to late first millennium BC and the medieval period, providing new insights into the metallurgical tradition that inspired such admiration in the Graeco-Roman world. These results have implications for the smelting of iron in liquid state, although it remains unclear where and when this technology first appeared in Western Eurasia.

Antiquity, 2019

The South Caucasus has been largely absent in broader discussions of prehistoric population aggre... more The South Caucasus has been largely absent in broader discussions of prehistoric population aggregation in Greater Eurasia. The authors use remote sensing, surface collection and mag-netometry to investigate two hilltop fortress settlements at the margins of the Kura River Basin, with a particular emphasis on satellite settlements around the main hills. The results support a model of settlement growth in which previously mobile groups settled around the fortress, while maintaining a degree of spatial and social separation. The use of multiple survey techniques reveals a complex picture of settlement organisation, with implications for comparative analysis of prehistoric population aggregation models.

Journal of Archaeological Research, 2019

This review synthesizes field research, textual analysis, and archaeometric data to evaluate diff... more This review synthesizes field research, textual analysis, and archaeometric data to evaluate different explanations for the spread of iron in the ancient Near East. Current evidence supports an Anatolian origin for extractive iron metallurgy on a limited scale sometime in the early 2nd millennium BC. However, the first major expansion of iron, both in Anatolia and across the wider Near East, occurred in the late second and early first millennium BC. Explanations that place iron adoption within its broader social context are favored over those that consider material or geological properties in isolation. A recurring theme is the importance of comparative analysis, both geographically and between the iron and bronze economies, to explore how social, political, and economic conditions affected adoption patterns.

Radiocarbon, 2018

The Eastern Black Sea region of the South Caucasus contains an extremely rich record of metallurg... more The Eastern Black Sea region of the South Caucasus contains an extremely rich record of metallurgical remains that is poorly known outside of the former Soviet Union. Large numbers of relatively small smelting sites dot the foothill regions, forming a dispersed, yet large-scale metallurgical landscape. New fieldwork in the region has followed up on earlier Soviet period research, relocating and reanalyzing previously known sites and identifying new ones. This paper presents a series of 33 radiocarbon (14C) dates from copper and iron smelting sites in this region. Dates from copper smelting sites suggest that copper smelting occurred over a shorter and more intense period than previously thought, between about 1300 and 800 BC. Dates from newly discovered iron smelting sites place these activities in two episodes during the Classical-Hellenistic period (ca. 500–200 BC) and the High Medieval period
(ca. AD 1050–1400). The dramatic expansion in bronze production immediately prior to the adoption of iron mirrors patterns in other regions of Europe and the Near East, and has implications for understanding the economic contexts in which iron emerged. While the new dates from iron smelting sites provide only an initial outline of the iron production chronology in the region, they represent an important step for resolving outstanding issues from previous investigations.

Despite the large numbers of ancient mining and metal production sites in the South Caucasus, spa... more Despite the large numbers of ancient mining and metal production sites in the South Caucasus, spatial analyses of metal production landscapes are far from common. Archaeological survey in the ore-rich foothills of Kvemo Kartli, southern Georgia, demonstrates the potential for integrating previous geological and archaeological research into present-day landscape archaeology projects. Combining reports of earlier excavations, satellite imagery and ground-level observations, 15 hilltop sites and 9 sites with possible mining activity were mapped. Systematic surface collection revealed that most of these hilltop sites contain at least some traces of Late Bronze–Early Iron Age (LBA–EIA, c. 1500–600 BC) habitation, with a number of sites having a predominantly LBA–EIA ceramic assemblage. The relative positioning of hilltop settlement and mining sites shows that settlement sites were frequently positioned in ways that controlled access to ore deposits. Metallurgical activity, evidenced by the presence of slag, was attested at several of these hilltop sites. In one or two cases, settlements were built directly adjacent to ore deposits. However, it remains an open question whether proximity to ore deposits and evidence of metal production at these sites meant that metal production was administered or managed by elites within those communities. Detailed investigation of the spatial contexts of metal production at all spatial scales is necessary for understanding the factors driving social and technological change during this period.

Studies of metal production frequently show a correlation between scale and organizational comple... more Studies of metal production frequently show a correlation between scale and organizational complexity.
The remarkably rich landscapes of metal-producing sites of late 2nd-early 1st millennium BC Colchis provide
an unprecedented opportunity to reexamine this apparent correlation. Investigations of copper
smelting sites show that industries with a large aggregate output can be the result of numerous small
groups of metalworkers acting independently. Spatial data on site distributions, estimates of productive
output, and archaeometric data on ore procurement patterns were integrated to reconstruct the organization
of production. Judicious use of a portable X-ray fluorescence spectrometer (pXRF) showed that not
only were smelting sites highly dispersed, but also that metalworkers at different sites were using ores
from geologically distinct deposits. This innovative approach helped to reconstruct the organization of
production in a distinctive metal production landscape, bridging an enduring divide between
landscape-scale and microscopic investigations of craft production.

A B S T R A C T Understanding the spatial distribution of different craft production activities i... more A B S T R A C T Understanding the spatial distribution of different craft production activities is an essential part of any investigation into the organization of production. In the Iron Age southern Levant, discussions of the rise of iron often revolve around the relative organization of bronze and iron production. For these reasons, identifying where different stages of metal production occurred is essential for testing models of technological change during this period. This study reviews the challenges of identifying different stages of metal production from often-ephemeral residues found at settlement sites, with particular emphasis on the question of urban iron smelting in the early Iron Age southern Levant. These considerations are applied to the analysis of a small but significant assemblage of metal production remains from Iron IIB Ashkelon (c. 8th century BCE), using macroscopic observations, chemical analysis, and microscopy. The results of these analyses support the conclusion that multiple iron production processes—likely including both smelting and smithing—took place in or near a domestic quarter at Ashkelon. With one or two exceptions, copper production residues are restricted to secondary refining and casting residues. Copper smelting was carried out elsewhere. If this pattern holds as more urban production debris is recognized and analyzed, such differences in the relative organization of iron and copper-alloy production may provide clues as to why iron production expanded dramatically in the early 1st millennium BCE.

The South Caucasus was a major center of metal production in the Late Bronze and Early Iron Ages.... more The South Caucasus was a major center of metal production in the Late Bronze and Early Iron Ages. Nowhere is this more clear than in the hills and mountains in the southeastern Black Sea region (ancient Colchis), where exceptionally large numbers of metal production sites have been found. Chemical and microscopic analysis of slagged technical ceramics at these sites illuminates several aspects of both raw copper and tin bronze alloy production. Copper ores were smelted in a complex multi-stage process designed to extract metal from sulfide ores. Technical ceramics served as containers for a range of different reactions, from the first phase of smelting, in which the copper sulfides were likely consolidated into a matte, though later stages of matte processing and metal copper production in smaller crucibles. In addition, a single crucible fragment, recovered from a late 2nd millennium BC slag heap, demonstrates that tin bronze was created by the direct addition of cassiterite tin ore, probably of alluvial origin, to metallic copper. The crucible's context, the use of cassiterite ore rather than tin metal, and a review of local geology suggests that the tin used in this crucible came from nearby, with the most likely source being the Vakijvari and Bzhuzhi gorges roughly 10-15 km away. While a single fragment does not speak to the regularity of this practice, at the very least it raises the possibility that the Colchian bronze industry was based on local rather than imported tin.

Landscape-scale survey data are rarely combined with chemical and microscopic analyses in archaeo... more Landscape-scale survey data are rarely combined with chemical and microscopic analyses in archaeological research. Here, I present two case studies integrating data with widely varying spatial scales to address questions about metal production and consumption in South Caucasus c. 1500-500 BC.

For a variety of historical reasons, the interdisciplinary field of innovation diffusion research... more For a variety of historical reasons, the interdisciplinary field of innovation diffusion research has been
underutilized by archaeologists examining technological change. Yet there is much to be gained by
engaging with the predictive models produced by hundreds of investigations of technology adoption.
Using the case of iron adoption in Western Asia, I demonstrate how an approach utilizing these
concepts, with some modifications, provide a more complete perspective on technological change.
Innovation-diffusion theory identifies both structural factors (e.g. the nature of interaction networks
and the presence of so-called "opinion leaders") and innovation-specific features (e.g. an innovation's
observability and compatibility) that influence the pace and pattern of adoption. Using these concepts, I
examine patterns of metal usage and the economic structure of metal production on the southeastern
Black Sea coast in the late 2nd and early 1st millennia B.C. Archaeological evidence demonstrates that
iron, when it appears, was made with great skill and used in large quantities in ways that were probably
highly socially visible. I argue that concepts from innovation-diffusion theory explain these patterns
more effectively than approaches which attempt solely to identify relative advantages of iron over
copper alloys in terms of efficiency or mechanical effectiveness.

Metal production debris is usually quite rare in most excavations, and recognition and interpret... more Metal production debris is usually quite rare in most excavations, and recognition and interpretation of debris is often challenging. On the other hand, chemical and microscopic analyses require significant time investment and/or cost per sample, and the often destructive nature of analyses frequently limits the number of analyses. The result is that archaeologists studying ancient metal production are often confronted with small, spatially-limited datasets, and the analytical approach is intensive rather than extensive. As a result, archaeometric and spatial datasets are rarely combined in ways that address broad archaeological questions about the organization of production and the nature of ancient economies.
In this talk, I discuss several ways in which analytical and spatial data can be combined to address questions of the organization of production and technological change in the eastern Black Sea region during the Late Bronze and Early Iron Age. Analysis of metal production debris from an exceptional copper smelting landscape allows us to examine the degree of coordination of activities between sites, and presents a picture of large-scale bronze production that differs significantly from traditional models. Meanwhile, mapping compositional variation of copper-alloy artifacts helps address questions of metal supply and technological change at the end of the Bronze Age.

Between about 1500 and 500 BC, metallurgy in the South Caucasus underwent a series of dramatic tr... more Between about 1500 and 500 BC, metallurgy in the South Caucasus underwent a series of dramatic transformations. These transformations included the appearance of a new metal (iron), the disappearance and subsequent re-appearance of another (gold), as well as significant transformations in manufacturing technologies and the scale of production of a third (copper alloys). These technological trajectories converge and diverge in ways that defy unilinear, monotonic technological narratives. This talk sketches out the changing patterns of production and use of these three metals using a range of different types of evidence.

Copper-alloy manufacture witnessed a dramatic increase in the aggregate scale of production in the late 2nd millennium BC. Both the range of artifact types and the complexity of their manufacture increases, as does the overall quantity of copper-alloy metal in circulation. Cu-Sn and Cu-As alloys predominate, but unalloyed copper and some more exotic alloys such as Cu-Sb are also found. While the Caucasus has long been identified as a major source of copper, recent work has suggested that some local tin exploitation also occurred in the late 2nd millennium BC.

Intriguingly, the increase in the aggregate scale of production was not associated with the centralization in the administration of the copper smelting industry. Integration of chemical and spatial data shows that individual copper smelting sites remained small, probably seasonal enterprises, and that metalworkers at contemporary, neighboring smelting sites were supplied with ore from geologically distinct ore sources. Casting, forging, and the manufacture of artifacts also took place at numerous sites, with little evidence of centralization or nucleation of secondary production activities.

Sometime after the turn of the 1st millennium BC, iron artifacts began to be used with increasing regularity. While the current understanding of the timing and pace of iron adoption likely requires significant refinement, a general picture has started to emerge. It is clear that a major increase in the use of iron occurred in the 8th-6th centuries BC, somewhat later than elsewhere in southwest Asia. Though the existence of an elaborate bronze industry seems to have delayed the initial adoption of iron, early iron artifacts nonetheless mimic those of bronze, and bimetallic artifacts are common. At least initially, iron- and bronze-working were very closely linked, and the expansion of iron should be understood as closely connected to the expanding appetite for metal that characterized this period.

Gold use, on the other hand, follows a technological trajectory that diverges significantly from that of copper alloys. Gold extraction in the Caucasus began by 3000 BC (Early Bronze Age), but the early fluorescence of gold production in the South Caucasus took place in the Middle Bronze Age (c. 2400- 1500 BC). However, sometime around the mid-second millennium BC—at around the same time that the complexity and scale of copper alloys expanded—gold drops out of the metallurgical repertoire. This technological abandonment is particularly intriguing given that the Late Bronze Age societies showed a clear appetite for gold-colored objects, as demonstrated by their preference for tin bronze in prestige items and weaponry. It is only later, in the 8th-6th centuries BC, that gold-working reappears in the region, fueling Greek imagination of the region as the home of the legendary “Golden Fleece.”

This comparative examination reveals the complicated nature of metallurgical change in the South Caucasus. Metallurgical change cannot simply be characterized as a unilinear progression from technologies involving less technical skill to those involving more technical skill. As such, the Caucasus provides an opportunity to re-think models of metallurgical development across the broader Eurasian sphere.