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Introduction
Recent investigations of archaeological remains
from the Northern Isles of Scotland have indicated
that the Viking incursions and later Norse settlement
on the islands led to novel patterns of economy and
subsistence. Although debate continues regarding
the nature of the early interaction between the native
Picts and these Viking incomers (Barrett et al.
2000, Crawford 1981, Morris 1996, Ritchie 1974),
novel settlement patterns and more intensive marine
exploitation, leading to eventual trading and
exportation of marine resources, are clearly visible
(Barrett 1997; Barrett and Richards 2004; Barrett
et al. 2000, 2001; Cerón-Carrasco 2005; Graham
Campbell and Batey 1998:214–215) and are testimony
to Scandinavian influence on the islands. On
the Outer Hebrides, on the other hand, it has been argued
that settlement patterns succeeding the Pictish
period do not demonstrate such profound changes
to Iron Age settlement patterns, with some level
of continuity postulated as opposed to a swift and
violent population replacement (Sharples and Parker
Pearson 1999; though see Sharples and Smith 2009).
Nonetheless, changes in economic patterns, namely
increased and more specialized marine product exploitation
during the Norse period are likely (Smith
and Mulville 2004:55).
Here we provide new evidence for dietary and
economic patterns during the Late Iron Age and
Norse period by exploiting biomarkers preserved in
absorbed and visible residues from a large number
of pottery sherds excavated from Late Iron Age and
Norse contexts from Bornais, on South Uist (131
vessels), and Late Norse pottery from Jarlshof, on
Shetland (27 vessels). This approach offers a very
high level of sensitivity for the detection of marine
product processing and furthermore allows the
exploitation of secondary (e.g., dairy) products to
be directly demonstrated. These new findings demonstrate
distinct patterns of resource processing in
pottery at these two island locations.
Investigation of Organic Residues in
Archaeological Pottery
The investigation of preserved ancient biomolecules
can offer new insights into the substances processed
or contained in unglazed vessels. This knowledge,
in turn, can lead us to answer questions of wider
archaeological significance, including resource exploitation
strategies, long-distance trade links, cultural
practices, and long-term dietary patterns. It is well
established that lipid components become absorbed
and protected within the ceramic matrix of unglazed
pottery, with a negligible contribution of lipid from
the burial environment (Heron and Evershed 1991).
After the extraction of biomolecules using organic
solvents, diagnostic components in these residues can
be related to distributions identified in modern reference
plant and animal products. However, the specificity
of identification is dependent upon the degree of
uniqueness of these biomarkers (biological markers)
to particular resources, and the persistence of these
or their degradation products (Evershed 1993, 2008).
Hence, while beeswax, for example, contains characteristic
distributions of palmitate wax esters (e.g.,
Evershed et al. 1997), it is often difficult to distinguish
plant waxes of different origins due to the ubiquitous
nature of many plant wax components (Kolattakudy
et al. 1976, Tulloch 1976). On the other hand,
Contrasting Patterns of Resource Exploitation on the Outer Hebrides and
Northern Isles of Scotland during the Late Iron Age and Norse Period
Revealed through Organic Residues in Pottery
Lucy J.E. Cramp1,2,*, Helen Whelton1, Niall Sharples3, Jacqui Mulville2, and Richard P. Evershed1
Abstract - This paper presents the findings from an investigation of organic residues extracted from pottery sherds from
Late Iron Age and Norse phases from Bornais, South Uist, and the Late Norse period from Jarlshof on Shetland. These
data confirm intensive and/or specialized processing of marine products in pottery on Shetland, either for consumption or
other uses, such as rendering of oil from fish livers. In contrast, at Bornais, little increase in the intensity of marine product
exploitation can be identified between the residues from the Later Iron Age and Norse phases; however, an emphasis on
dairy products is identifiable throughout all phases and pottery types. While the findings from these two sites clearly cannot
be extrapolated as entirely representative of the wider respective regions, what emerges is further evidence for diverse
economic or cultural patterns at different locations within Scandinavian Scotland.
Special Volume 9:134–151
2010 Hebrideian Archaeology Forum
Journal of the North Atlantic
1Organic Geochemistry Unit, School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, UK. 2Current
address - Department of Archaeology and Anthropology, University of Bristol, 43 Woodland Road, Bristol BS8 1UU, UK.
3SHARE, Cardiff University, Colum Drive, Cardiff CF10 3EU, UK. *Corresponding author - lucy.cramp@bristol.ac.uk.
2015
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although modern dairy fats can be distinguished from
adipose fats with relative ease due to high abundances
of short-chain fatty acyl components in milk fats,
the preferential hydrolysis and loss of shorter-chain
components means such distributions are rarely well
preserved in an archaeological fat residue. As such, it
is necessary to investigate the stable carbon isotopic
composition of individual saturated fatty acid components
in order to separate milk from adipose fats, and
these from non-ruminant fats (Dudd and Evershed
1998, Dudd et al. 1999, Evershed et al. 2002).
Organic residues of aquatic origin are a strong
likelihood at later prehistoric coastal and island
sites and are a particular challenge to identify in
archaeological lipid extracts. This difficulty is due
to high abundances of long-chain polyunsaturated
fatty acids (PUFAs), such as eicosatetraenoic acid
(C20:4), eicosapentaenoic acid (EPA; C20:5) and docosahexaenoic
acid (DHA; C22:6) in marine and freshwater
lipids (Fig. 1A). These highly unsaturated
components are susceptible to rapid oxidation and
hence, loss, from the original fatty acid distribution,
resulting in a fatty acid distribution dominated by
the more stable saturated components, thus closely
resembling degraded terrestrial fats (Fig. 1B). It is
therefore necessary to exploit more stable products
that derive from the presence of double bonds in
the precursor fatty acids and, importantly, preserve
the carbon chain length of the original fatty acids.
Oxidation products, including mono- and dihydroxy
fatty acids, arise through the hydroxylation
of double bonds in monounsaturated fatty acids,
and the carbon chain length of these products therefore
reflects that of the precursor fatty acid, while
the position of the hydroxyl groups preserves the
position of the original double bonds. Chemical
bonding or adsorption of these components into an
insoluble polymeric matrix means it is often necessary
to perform an alkaline extraction in order to
release the “bound” lipids from the pottery fabric.
These derivatives have been successfully extracted
from archaeological pottery that was used to process
plant and marine products that would have originally
contained significant quantities of monounsaturated
fatty acids (Copley et al. 2005, Hansel and Evershed
2009, Hansel et al. 2011, Regert et al. 1998), and the
detection of longer-chain dihydroxy acids (>C20) is
diagnostic of an aquatic source.
Further evidence for a marine contribution to an
archaeological residue can be sought through the
Figure 1. Partial GC/MS total ion and mass chromatograms showing (A) the fatty acid composition of fresh limpet and
structure of C20:4 (n-6) fatty acid and (B) the fatty acid composition of limpet fat degraded in the laboratory at 270 °C for
17 h. (C) m/z = 105 selected ion monitoring (SIM) mass chromatogram, which is the fragment ion common to all APAAs,
showing distributions of C18 (M+.290), C20 (M+.318) and C22 (M+.346) ω-(o-alkylphenyl)alkanoic acids present in (B) and the
structure of a C20 APAA (n-0). Fatty acids were analyzed as their methyl esters.
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identification of ω-(o-alkylphenyl)alkanoic acids
(APAAs) that form from the thermal degradation of
polyunsaturated fatty acids (Matikainen et al. 2003).
We have demonstrated via heating experiments of
pure fatty acid standards and mixtures of fatty acids
that the carbon chain length of these products
reflects that of the precursor fatty acids (Cramp and
Evershed 2014, Evershed et al. 2008), and therefore
the detection of C20 and C22 APAAs in archaeological
residues is evidence that products containing longchain
polyunsaturated fatty acids (i.e., marine fats
and oils) were processed in the pottery (Copley et
al. 2004, Evershed et al. 2008, Hansel et al. 2004).
APAAs are only likely to be present in extremely
low concentrations, but by operating the mass spectrometer
in selected ion monitoring (SIM) mode, it
is possible to detect these diagnostic compounds at
very high sensitivity (Fig. 1C).
In addition, a third class of biomarker, isoprenoid
fatty acids, is also a diagnostic of marine fats and
oils. This class of compounds is not a product of
degraded unsaturated fatty acids but rather derives
from phytol in marine algae, accumulating in organisms
further up the food chain. The presence of one
or more of the isoprenoid fatty acids 4,8,12-trimethyltridecanoic
acid (4,8,12-TMTD), 2,6,10,14-tetramethylpentadecanoic
acid (pristanic acid), and
3,7,11,15-tetramethylhexadecanoic acid (phytanic
acid) may therefore be observed in residues of a
marine origin. However, since at least some of
these isoprenoid fatty acids (e.g., phytanic acid) are
known to also exist in terrestrial fats such as milk
(Vetter and Schröder 2011), these are not robust biomarkers
in isolation.
At the Late Iron Age and Viking/Norse island
settlements investigated here, likely resources
include domesticated and wild ruminants (including
cattle, sheep, and red deer), some pig, marine
shellfish, fish, marine mammals, cultivated cereals,
and other wild and domesticated plants. Through
the investigation of distributions of biomolecules,
including the use of SIM to detect those present
only in low concentrations, in combination with the
determination of stable carbon isotope compositions
of individual fatty acids, it is possible to determine
the origins of the major sources of lipids recovered
from this pottery in addition to some of the more
minor commodities that may have been more sporadically
processed. The aim of the research presented
here was to reconstruct key aspects of these
island economies and, especially, to investigate the
changing importance of marine products (e.g., fish,
shellfish, marine mammals) from the Late Iron Age
to the Norse period, through the investigation of
biomarkers preserved in the cooking pottery used by
the inhabitants of these settlements.
Pottery Investigated
The settlement at Bornais is located on the machair
plain of the western coast of South Uist, which
forms part of the island chain of the Outer Hebrides
off the western coast of Scotland (Fig. 2). It is a multiphase
site, first settled during the Middle Iron Age
(AD 200–400) and inhabited throughout the Late
Iron Age (5th–8th century AD), Viking (9th–10th century),
and Norse period (10th–14th century), showing
a decline by the 15th century AD. The site comprises
three large mounds (1, 2, and 3) and two subsidiary
mounds (2A and 2B). Exploratory excavations were
undertaken on mounds 1 and 3, while mound 2 and
mound 2A have seen substantial area excavations
(Sharples 1999, 2000, 2005; Sharples and Smith
2009). Although all mounds produced evidence for
Norse activity, a Late Iron Age wheelhouse was excavated
on mound 1. Mound 2 appears to have been
the center of the settlement and revealed a sequence
of three substantial buildings, including a large bowshaped
hall dating to the 11th century. While mound
2A also contained a sequence of buildings, the focus
of this excavation was upon the associated ancillary
structures and middens.
The excavations at Bornais produced rich cultural
and ecofactual material, including worked bone objects,
pottery, carbonized plant remains, and faunal
assemblages. Objects including steatite bowls, glass
beads, metalwork, and walrus ivory are indicators of
trade links with Shetland, Scandinavia, England, and
Ireland (Sharples 2000). However, although ceramic
forms underwent a significant change with the Norse
period, it has been argued that the continued use of
ceramics per se and the similarity between Late Iron
Age and Viking settlement patterns and architectural
features suggest a significant continuity of the
indigenous Pictish population during the Viking age
(Sharples and Parker Pearson 1999). From the large
pottery assemblages excavated, 131 sherds and any
associated carbonized residues from Mounds 1, 2,
2a, and 3 were investigated. These sherds date from
the Late Iron Age through to the Late Norse period
and, as such, were grouped according to phase, comprising
Late Iron Age I (5th–6th century AD), Late
Iron Age II (Pictish; 7th–8th century AD), Early Norse
(10th–early 11th century AD), Mid-Norse (Late 11th–
12th century AD), and Late Norse (13th–14th century
AD) vessels. Sherds were selected from the major
vessel forms, including jars and bowls. Alongside
these probable “cooking pots”, 13 distinctive Middle
and Late Norse “platters” were included for comparison.
While also colonized by the Vikings, the
Northern Isles of Scotland, including Shetland and
Orkney, and the northeast mainland of Scotland,
comprised a region that can be distinguished in
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chronology, environment, and culture from the
Outer Hebrides, with persuasive evidence for the
Viking introduction of a strongly marine-based
subsistence strategy and economy (Barrett et al.
1999, 2001). The Pictish period on the Northern
Isles is succeeded by the Viking Age at ca. 800 AD,
with the Norse period continuing from the 11th–
14th century AD. Jarlshof, located near Sumburgh
Head on the southern tip of Shetland (Fig. 2) has
revealed extensive Viking and Norse remains which
succeed substantial prehistoric activity. The earliest
evidence dates to the Neolithic, and occupation
continued through the Bronze and Iron Ages to the
numerous rectilinear structures that are associated
with Scandinavian settlers. The Jarlshof site continued
to be inhabited during the Medieval and post-
Medieval era until the 17th century when the large
“Laird’s House” was abandoned.
Although at Jarlshof the Viking and Norse remains
are extensive, it is unlikely this settlement
was ever a large village. It is more probable that the
excavated buildings were occupied during successive
phases over several centuries, each of which
saw new modifications and additions to the settlement
plan. Rich cultural remains were excavated,
and yet because systematic wet sieving was not
undertaken, the environmental remains are unfortunately
biased, and limited, due to the nature of
their recovery. With a preference for steatite, rather
than ceramic vessels during the Viking period at
Jarlshof, pottery only re-emerged relatively late in
the sequence of Norse activity (Hamilton 1956:188,
Figure 2. Map of the British Isles showing locations of sites d iscussed in the text.
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Ritchie 1977). The pottery analyzed here therefore
mainly derived from phases VII and V (approximately
12th–13th century AD; Hamilton 1956), and is
probably contemporaneous with the pottery from the
Mid- and Late Norse period at Bornais, which spans
the 11th to 14th century. This pottery is relatively
crude, grass-tempered hand-made ware, including
Hamilton’s “Class II”, described as a “large open
bowl” (Hamilton 1956:188).
The sherds selected are described in Table 1,
which includes a summary of the phases and forms
included in the study. Where possible, sherds were
selected from the upper body of the vessel, since this
part of the vessel is likely to contain the highest concentrations
of lipid (Charters et al. 1993, 1997). Thick
visible carbonized encrustations were present on
the inner and outer surfaces of a large number of the
sherds. Portions of these residues were also removed
and analyzed alongside the absorbed residues. The
analytical and instrumental protocols are described in
Appendix 1. The istotope and marine biomarker data
for all of the sherds found to contain significant quantities
of lipid are presented in Appendix 2.
Findings
Late Iron Age to Late Norse pottery from Bornais
(AD 400–1400)
Organic residues were well preserved in the
absorbed and visible residues from Bornais, with
appreciable concentrations of lipid extracted from
60% of sherds. No lipids were extractable from the
Mid- and Late Norse platters included in the study,
suggesting that these vessel forms were used for
lipid-poor commodities, such as bread. Otherwise,
the majority of residues from Bornais were characterized
as degraded animal fat due to high relative
concentrations of stearic acid (C18:0 fatty acid) and
characteristic distributions of tri-, di-, and monoacylglycerols
(Fig. 3). A wide range of triacylglycerol
carbon numbers, with distributions closely resembling
partially degraded dairy fats (Christie 1978,
1981; Dudd et al. 1998; Evershed et al. 2002), was
observed in many sherds from the Late Iron Age
through to the Late Norse period. The determination
of stable carbon isotope values of individual fatty
acids from 78 residues confirms that, in fact, 35% (n
= 11/31) of Late Iron Age I and II residues and over
50% (n = 24/47) of Early to Late Norse residues from
Bornais lie within the range expected for dairy fats
(Figs. 4, 5; Copley et al. 2003 ). Dairy fats could not
be related to any specific vessels, being present in all
identifiable types (excepting the platters), including
open and convex bowls and jars. The analysis of faunal
remains from Bornais indicates that ruminants, in
particular, cattle, sheep, and deer, were a significant
contributor to the diet at Bornais, and the high number
of neonatal domesticates observed, particularly
among cattle assemblages, is indicative of a dairying
economy in both the Late Iron Age and Norse
periods (Mulville 1999). The faunal bone age indicators
produced conflicting interpretations regarding
whether the highest frequency of neonates lay in
the Late Iron Age or Norse periods (Mulville 1999),
with dental evidence suggesting greater emphasis in
the Late Iron Age compared with the Norse period,
and bone-fusion evidence suggesting the converse.
The residues analyzed here are certainly supportive
Table 1. Identities of the sherds investigated from each major phase of the settlement at Bornais and Jarlshof, noting any characteristic forms.
No. analyzed
Visible No. δ13C
Phase Sherds residues determinations Forms identified
Bornais
Late Iron Age (5th–8th century AD) 4 2 0 Jars (n = 3; globular and shouldered); bucket (n = 1)
Late Iron Age I (5th–6th century AD) 20 3 6 Shouldered jar (n = 3)
Late Iron Age II (7th–8th century AD) 25 20 25
Total 49 25 31
Early Norse (10th–11th century AD) 25 10 19 Open -mouth bowl (n = 1), platter (n = 1)
Middle Norse (Late 11th–12th century AD) 25 9 13 Platters (n = 7), convex bowls (n = 3),
open-mouth bowls (n = 3)
Mid-Late Norse (Late 11th–14th century AD) 4 - 4
Late Norse (13th–14th century AD) 24 6 9 Platters (n = 3), convex bowls (n = 2)
Norse (10th–14th century AD) 4 1 2 Platters (n = 3)
Total 82 26 47
Jarlshof
Late Norse, House 5 (12 th–13th century AD) 10 4 8 Square mouthed bowl (n = 1)
Late Norse, House 7 (12 th–13th century AD) 12 - 11 Round bowls (n = 12)
Late Norse (12th–13th century AD) 5 1 3
Total 27 5 22
Total 158 56 100
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30% (n = 20) of Early Norse, 13% (n = 15) of Mid-
Norse, 50% (n = 4) of Mid–Late Norse and 28% (n
= 18) of Late Norse vessels investigated using SIM.
Long-chain dihydroxy fatty acids were identified in
≈40% of “bound” lipids subsequently extracted from
these sherds (Figs. 4, 6). These findings confirm that,
in addition to ruminant products, marine resource
exploitation can be identified in both the Late Iron
Age II and subsequently throughout the Norse period.
Although a broad increase in the frequency of
marine biomarkers between the Late Iron Age and
Norse phases can be observed, there is actually only
a slight increase in evidence for marine product exploitation
between the Late Iron Age II and the Early
Norse period, and there is not an increasing trend in
the frequency of marine biomarkers throughout the
Norse period. Thus, there is no clear association of
marine product intensification with the beginning of
the Viking age.
of intensive exploitation of dairy products during
both the Late Iron Age and the ensuing Norse period,
and the higher frequency of residues of dairy origin
during the Norse period lends greater support to the
bone-fusion rather than the dental evidence.
Although the compound-specific stable carbon
isotope values indicate that predominantly terrestrial
resources were prepared in the pottery vessels from
all phases investigated at Bornais, substantial quantities
of marine fat would be required to significantly
shift these values, such that lower quantities of
aquatic products may be undetectable. Therefore,
solvent- and alkaline extracted residues were analyzed
using GC/MS operating in SIM mode in order
to detect other marine biomarkers that might be present
only in very low concentrations, including ω-(oalkylphenyl)
alkanoic acids (APAAs) and dihydroxy
acids. Although no long-chain APAAs were detected
in the Late Iron Age I pot residues (n = 8), these were
identified in 20% (n = 25) of the Late Iron Age II,
Figure 3. Partial high-temperature gas chromatograms from trimethylsilylated lipid extracts from the sherd fabric and its carbonized
deposit from Bornais. X:Y FA–free fatty acid, where X is the number of carbon atoms and Y the degree of unsaturation.
X MAGs–monoacylglycerols, X DAGs–diacylglycerols, X TAGs–triacylglycerols, with X number of acyl carbon atoms.
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Figure 4. Scatter plots of the δ13C values of the major fatty acids (C16:0 and C18:0) in the archaeological lipid extracts from
Bornais, Late Iron Age I (a), Bornais, Late Iron Age II (b), Bornais, early Norse (c), Bornais, Mid-Norse/Mid–Late Norse
(d), Bornais, Late Norse (e), and Jarlshof, Late Norse (f). Note the offset of the lipid extracts from the reference ellipses,
resulting from a marine signal causing enrichment in values. These solid ellipses are derived from modern UK terrestrial
and marine fauna and are corrected for the effect of the release of δ13C-depleted post-industrial carbon CO2 (+1.2 ‰; Friedli
et al. 1986). Since atmospheric carbon may not yet be fully mixed in deeper oceans, it is possible some deep-ocean feeders
have values closer to the uncorrected values. indicates where biomarkers indicative of a marine origin were also
detected in the residue.
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Later Norse pottery from Jarlshof (AD 1100–1300)
Organic residues were particularly well-preserved
in the absorbed and visible residues from
Jarlshof, with appreciable concentrations of lipid
extracted from >70% of sherds and 60% of carbonized
deposits. The TLEs were usually dominated
by the C16:0 and C18:0 fatty acids (Fig. 6); however,
in contrast to lipid extracts from Bornais, the C16:0
fatty acid was the major component in the majority
of residues. Traces of long-chain (≥C20) monounsaturated
fatty acids were also widely present
in low concentrations. Based upon the fatty acid
composition alone, a high proportion of these residues
do not resemble terrestrial animal fats. Fifteen
of twenty-two sherd residues analyzed using SIM
(68%) contained long-chain APAAs and long-chain
dihydroxy fatty acids (Figs. 4, 5, 6). Isoprenoid fatty
acids were present in some residues containing other
marine-derived biomarkers, albeit in low concentrations;
thus far, all three of the diagnostic isoprenoid
acids have been identified in only one residue from
Jarlshof (Figs. 7,8).
The stable carbon isotope values of individual fatty
acids were also determined from these 22 residues,
with approximately half yielding δ13C values that are
more enriched than anticipated for purely terrestrialderived
fats (Fig. 4), providing further confirmation
of a marine contribution. However, while some residues
exhibit values consistent with a pure marine fat
origin, approximately half plot along a mixing line,
indicating some contribution of terrestrial fats to a
mixture. Plotting the Δ13C (δ13C18:0–δ13C16:0) values,
which removes effects of climate and environment
on absolute values, emphasizes the physiological and
metabolic differences between the animals producing
the fats (Fig. 5). When plotted in this way, twelve of
these residues could be characterized as reflecting a
contribution of ruminant fat, with two residues assigned
to a dairy fat source, and the remainder to carcass
fats. It cannot be discounted that the latter result
from the mixing of dairy and marine fats, resulting in
Δ13C values that lie within the intermediate ruminant
carcass fat range. Although the ecofactual evidence
from Jarlshof is sparse and little discussed in the
Figure 5. Plot of the difference between the δ13C values of C18:0 and C16:0 (Δ13C) which serves to classify the archaeological
lipid extracts from Jarlshof (a) and Bornais (b). The ranges on the y axis are derived from modern reference fats. Stars
indicate where aquatic biomarkers were also detected. The largest squares show the mean Δ13C and δ13C16:0 for a dataset
of modern marine fauna from the North Atlantic (n = 64; Cramp and Evershed 2014) and Neolithic ruminant carcass and
dairy fats. Due to the island location, which is known to result in more enriched terrestrial stable carbon isotope values
compared with non-island locations (Farquhar et al. 1989, Heaton 1999), the isotope values from routinely used UK datasets
of modern terrestrial fauna (Copley et al. 2003) are likely to have absolute δ13C16:0 values that are too depleted for direct
comparison here, although the Δ13C proxy, which reflects differences in metabolism, is known to be largely unaffected by
environmental variability (Dunne et al. 2012). Therefore, more appropriate end points for ruminant carcass fats and ruminant
dairy fats are derived from a large dataset of values from Neolithic pottery residues shown to contain no contribution
of aquatic fats, with Δ13C values of <-3.4‰ (dairy fats, n = 139) and Δ13C values of -3.4 to 0‰ (carcass fats, n = 78). Error
bars show one standard deviation.
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dominantly terrestrial-derived origin. Since there is
a relatively low abundance of stearic (C18:0) acid in
marine fats and oils, a low contribution of ruminant
adipose or dairy fat (i.e., <25%) would significantly
shift the δ13C18:0 values of a marine fat towards
a terrestrial signature, as modelled in Fig. 5. We
would suggest, therefore, that mixing with terrestrial
fats in the majority of vessels was relatively minor
to retain generally elevated δ13C and Δ13C values.
The high prevalence of aquatic biomarkers and
enrichment of stable carbon isotope values leads us
to conclude that in contrast to both Late Iron Age
and Norse pottery vessels from Bornais, marine
excavation report, it has been recognized that the
bones of very young animals were relatively frequent,
and reassessment of these remains has suggested a
dairying strategy—a pattern that has been identified
at other Late Norse sites on Shetland such as Sandwick
(Bigelow 1985). These data presented here do
not entirely contradict this interpretation; however,
compared with the residues from Bornais, there is a
less noticeable emphasis on dairy products in these
particular vessels from Jarlshof, perhaps arising from
considerably greater processing of marine products.
Only three residues displayed δ13C values and
biomarker evidence that was consistent with a pre-
Figure 6. Gas chromatograms showing typical fatty acid distributions from Jarlshof and (inset) the identification of three
isoprenoid fatty acids in this residue. Fatty acids were analyz ed as their methyl esters.
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Discussion
Faunal evidence from the Outer Hebrides has
suggested that an increase in the intensity of, and
investment in, marine product exploitation is associated
with the advent of
the Viking period (Ingrem
2005, Smith and Mulville
2004). However, at Bornais,
where pottery sherds
investigated span the Late
Iron Age through to the
end of the Norse period,
the transition to an increasingly
marine-based
economy is not strongly
supported by the findings.
Where identified, biomarkers
of aquatic origin most
frequently occurred mixed
with terrestrial products.
This finding is significant,
implying that at Bornais
cooking pots were relatively
versatile or, at least,
that these different ingredients
were prepared
together, with almost no
evidence for specialized
marine-product vessels.
Although a broad increasing
trend can be identified
when comparing the
Late Iron Age and Norse
periods, the frequency of
marine biomarkers in the
Middle Norse phase is
actually lower than that
observed during the Late
Iron Age II, and therefore
no clear shift towards an
increasingly marine-based
economy is observed. The
large number of organic
residues and range of
pottery types investigated
from Bornais, comprising
the further analysis of 93
residues from >150 vessels,
suggests that this is
representative of a wider
phenomenon, whereby
the exploitation of marine
products in pottery vessels
was not intensive, and
increased little during the
Norse period.
resources were widely and intensively processed in
pottery at Jarlshof, both exclusively in some vessels
and occasionally along with the processing of
terrestrial products in other pots.
Figure 7. GC mass chromatograms showing the relative intensity of ions diagnostic of
C18-C22 dihydroxy fatty acids. For the positive identification of C18, C20, and C22 dihydroxy
acids, identical chromatographic peaks must be present for all of the following ions: C18:
m/z 215, 317, and M[-15]+ 517; C20: m/z 215, 345, and M[-15]+ 545; C22: m/z 243, 345, and
M[-15]+ 573.
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Figure 8. GC mass chromatograms showing the relative intensity of ions diagnostic of (C18-
C22 ω-(o-alkylphenyl)alkanoic acids. For the identification of ω-(o-alkylphenyl)alkanoic
acids, identical chromatographic peaks must be present for the following ions: C18: m/z 105
and M+.290; C20: m/z 105 and M+.318; C22: m/z 105 and M+.346.
Although this might appear at odds with the faunal
data, this pattern may perhaps be explained in the
context of the cultural and economic context in this
region. Firstly, analysis of faunal remains from Bornais
have suggested that novel subsistence strategies
introduced in the Norse period included intensive
herring exploitation, a species uncommonly recovered
from Norse sites on the Northern Isles (Ingrem
2000, 2005:157). This finding leads us to speculate
whether herring specialization may have resulted
in the low visibility of marine products in organic
pottery residues from Norse-period pottery from
Bornais. There is some evidence from Bornais that
herring were preserved (Ingrem 2005:176), for example
by salting, drying, or smoking. If hung to dry
or smoke, this may have left little trace in pottery
residues, while soaking in brine is traditionally performed
in wooden barrels. The pottery residues from
the Norse phase at Bornais
would not reveal a
shift in fishing practices
if aquatic products were
being processed using
such methods, and it is
possible, therefore, that
an increase in marine
resource processing is
actually under-represented.
Secondly, a higher
degree of population
continuity in this
region, as argued by
Sharples and Parker
Pearson (1999), would
also explain a less emphatic
shift in dietary
and economic practices.
Evidence from northern
Scotland, on the other
hand, suggests profound
palaeoeconomic
changes occurring at the
beginning of the Viking
Age, moving from relatively
low importance of
marine products in the
late Iron Age (Barrett
and Richards 2004) towards
deep-water fishing
and greater exploitation
of large gadids
(Barrett 1997; Barrett et
al. 1999, 2001; Bigelow
1985; Hamilton 1956;
Nicholson 1998; Ritchie
1977), with representation
of mammal bones
decreasing respectively
(Barrett et al. 1999).
Deposits likely relating
to more intensive fishproduction
sites, possibly
for trade and export,
alongside increasingly
Journal of the North Atlantic
L.J.E. Cramp, H.Whelton, N. Sharples, J. Mulville, and R.P. Evershed
2015 Special Volume 9
145
enriched stable isotope values from Viking and Early
Medieval bone collagen from Orkney, suggest a second
phase of intensification in fish exploitation from
the 11th–14th centuries AD (Barrett and Richards
2004; Barrett et al. 1999, 2000). Also of note is that
the preference of species on the Northern Isles shifted
towards larger, deep-sea fish such as cod, saithe,
and ling (e.g., Barrett et al. 2001, Bigelow 1985,
Nicholson 1998, Richie 1976), which were more
likely butchered and cooked in pots than smaller
fish such as herring, thus increasing their visibility
in pottery residues.
Thus, it is perhaps unsurprising that the lipid
residues from Jarlshof on Shetland can readily be
distinguished from contemporaneous vessels residues
from Bornais Mid- and Later Norse vessels.
The lipid extracts exhibit more enriched stable carbon
isotope signatures alongside a very high prevalence
of well-preserved aquatic biomarkers. Dating
to the 12th–13th century AD, this pottery dates closely
to the “fish event horizon” on Orkney, whereby reintensification
of marine product exploitation has
been inferred at ca. 11th–12th centuries AD through
faunal remains and stable carbon isotope values,
likely arising from trade and export of dried fish
(Barrett 1997, Barrett and Richards 2004, Barrett
et al. 2000). There is convincing evidence for the
involvement of the Northern Isles of Scotland in the
North Sea fish trade at this time, although it is not
directly mentioned in historical records (Barrett et
al. 2000). Although the drying and/or export of large
amounts of fish might not leave direct traces in these
pottery vessels, it is still to be expected that, in the
context of significant intensification associated with
commercial fishing and the processing of large fish
on an industrial scale, marine products would likely
be readily available, particularly to those involved in
the trade.
Additionally, preparation of marine products
for non-dietary purposes, for example, for lighting
fuel, should be considered here. For example, boiling
fish livers for lamp oil has been hypothesized
from fragments of Nose-period vessels identified
at Underhoull on Shetland (Small 1966:242) and
ash deposits from St. Boniface on Orkney (Cerón-
Carrasco 1994). It is possible that certain vessels
from Jarlshof, specifically those with exclusively
marine-derived isotope signatures, were used in this
role, whether on a domestic or industrial scale. On
the other hand, this would imply that at Bornais rendering
marine oil through boiling in pottery vessels
was not commonplace until post-Medieval times
when rendering fish livers in cooking pots is known
to have been practiced on the Western Isles (e.g.,
McGregor 1880). Non-ceramic vessels that might
have been used as an alternative are not known at
Bornais, and therefore, while wood is a possibility,
it is also likely that another substance such as
ruminant tallow was collected or rendered for lighting
purposes on the Outer Hebrides, as identified in
Medieval lamps from Southern England (Mottram et
al. 1999).
Conclusions
The findings presented here lead us to conclude
that there are explicit differences between the residues
investigated from the Outer Hebrides and the
Northern Isles of Scotland, the most obvious of
which is the high prevalence of marine-derived biomarkers
and marine isotopic signatures in residues
from Late Norse pottery from Jarlshof on Shetland.
This finding contrasts markedly with pottery lipid
extracts from all phases investigated from Bornais
on the Outer Hebrides, where a partial or exclusive
marine contribution was considerably less frequently
identified even from contemporaneous pottery
residues dating to the Mid- and Late Norse period.
This lack of marine evidence on the sherds may reflect
more intensive and specialized investment into
marine resource exploitation by the 12th century on
Shetland, and may be due to the types of fish being
processed and the purpose for which these products
were destined.
We have also observed a strong emphasis on
dairy products at Bornais. The residues from Jarlshof
only exhibited limited evidence of dairy product
processing, although the faunal remains are suggestive
that a dairying strategy was also practiced at this
settlement, and the Norse introduction of taxation in
butter would suggest that dairying was likely important.
However, since the majority of residues from
Jarlshof pottery seem to have been used heavily for
marine product processing, it is possible that milk
products were processed in another kind of vessel
not sampled. Ultimately, therefore, the question that
remains is whether the organic residues actually
reflect profound differences in the inhabitants’ diet
at these two settlements or whether they result from
different economic practices (e.g., production for
export) or different product-processing techniques.
Clearly, the data presented here represents only two
sites from what is a likely to be a highly complex
picture; however, it serves to highlight the differences
in practices that may be investigated at other
Norse settlements in Scotland.
Acknowledgments
We are grateful to Ian Bull, Alison Kuhl, and James
Williams of the NERC Life Sciences Mass Spectrometry
Facility for technical assistance and Marcus Badger for assistance
producing the maps. This research was funded by
Journal of the North Atlantic
L.J.E. Cramp, H.Whelton, N. Sharples, J. Mulville, and R.P. Evershed
2015 Special Volume 9
146
Copley, M.S., F. Hansel, K. Sadr, and R.P. Evershed.
2004. Organic residue evidence for the processing
of marine animal products in pottery vessels from
the pre-colonial archaeological site of Kasteelberg D
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and stable carbon isotopic investigations of organic
residues of plant oils and animal fats employed
as illuminants in archaeological lamps from Egypt.
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Cramp, L.J.E., and R.P. Evershed. 2014. Reconstructing
aquatic resource exploitation in human prehistory using
lipid biomarkers and stable isotopes. Pp. 319–339, In
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Dudd, S.N., and R.P. Evershed. 1998. Direct demonstration
of milk as an element of archaeological economies.
Science 282:1478–1481.
Dudd, S.N., M. Regert, and R.P. Evershed. 1998. Assessing
microbial contributions to absorbed acyl lipids
during laboratory degradations of fats, oils, and pure
triacylglycerols absorbed in ceramic potsherds. Organic
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Dudd, S.N., R.P. Evershed, and A.M. Gibson. 1999.
Evidence for varying patterns of exploitation of animal
products in different prehistoric pottery traditions based
on lipids preserved in surface and absorbed residues.
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interpretation of absorbed residues in archaeological
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1997. Fuel for thought? Beeswax in lamps and conical
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Evershed, R.P., S.N. Dudd, M.S. Copley, and A.J.
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NERC (NE/F021054/1). We would also like to thank Alison
Sheridan of National Museums, Scotland, for providing
archaeological material for sampling from Shetland; NERC
for partial funding of the mass spectrometry facilities at
Bristol (contract no. R8/H10/63; www.lsmsf.co.uk); Helen
Grant of the NERC Life Sciences Mass Spectrometry Facility
(Lancaster node) for stable isotopic characterization of
reference standards and derivatizing; and the two anonymous
reviewers for their helpful comments.
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Appendix 1. Methodology.
Extraction and derivatization of total lipid extracts
Any carbonized deposits visible on the inner or outer surfaces of the pot were first removed using a solvent-cleaned
scalpel, to be investigated alongside lipids extracted from the fabric of the pottery. The outer surfaces of a small area of
the pot sherds were then cleaned using a modelling drill fitted with an abrasive drill bit, to remove surface contamination
derived from the burial surroundings or lipids inadvertently introduced through post-excavational handling. Approximately
2 g cleaned sherd was removed with a chisel, and these sherds and portions of the carbonized residues were ground to a fine
powder using a mortar and pestle. Immediately prior to lipid extraction, 20 μg or 10 μg of a C34 n-alkane was added to the
crushed pot or carbonized residue, respectively, as an internal standard, and lipids were then extracted (2 x 10 ml CHCl3/
MeOH 2:1 v/v; sonication x 20 min). Aliquots of the resulting total lipid extract (TLE) were filtered through a silica column
and treated using 40 μl N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA; 70 °C, 1 h). Excess BSTFA was removed under
a gentle flow of nitrogen prior to dissolution of the residue in an appropriate volume of hexane.
Extraction and derivatisation of “bound” lipids
Base extractions to release the “bound” lipids were performed on ≈1 g previously solvent-extracted pottery. Five millilitres
0.5M NaOH/MeOH was added, and the mixture heated (70 °C, 1 h). After cooling to room temperature, the mixture
was acidified to pH 3 using 1 M aqueous HCl, and then the lipids extracted using 3 x 3 ml CHCl3. This fraction was analyzed
as TMS derivatives as described above.
Preparation of FAMEs
For the detection of isoprenoid and ω(o-alkylphenyl)alkanoic acids and the determination of the stable carbon isotope
composition of individual fatty acids, aliquots of selected TLEs were prepared for analysis via GC/MS, GC/MS-SIM, and
GC/C/IRMS as fatty acid methyl esters (FAMEs). Portions of lipid extracts were hydrolyzed using 2 ml 0.5 M NaOH/MeOH
(70 °C, 1 h). The mixture was cooled, and the neutral fraction extracted using 3 x 3 ml hexane. The sample was acidified to
pH 3 using 1 M aqueous HCl and the lipids extracted using 3 x 3 ml CHCl3. The hydrolyzed fatty acids were then methylated
using 100 μl BF3/MeOH (14% w/v; 75 °C, 1 h), and the FAMEs extracted using 3 x 2 ml CHCl 3.
High temperature gas chromatography (HTGC)
All archaeological total and “bound” lipid extracts were screened and quantified using an Agilent 7890 fitted with a
high-temperature non-polar column with a 100% dimethyl polysiloxane stationary phase (15 m x 0.32 mm i.d., 0.1 μm film
thickness). The temperature program comprised a 50 °C isothermal followed by an increase to 350 °C at a rate of 10 °C
min-1 followed by a 10-min isothermal.
Gas chromatography/mass spectrometry (GC/MS)
Base extracts were analyzed using a GC/MS fitted with a non-polar column for the identification of hydroxy fatty acids.
The instrument was a ThermoFinnigan single quadrupole TraceMS run in electron ionisation (EI) mode (electron energy
70 eV, scan range of m/z 50–650 and scan time of 0.6 s). Samples were introduced onto a non-polar column with a 100%
dimethyl polysiloxane stationary phase (CP-Sil CB, 50 m x 0.32 mm i.d., 0.12-μm film thickness) with an oven program
comprising a 2-min isothermal at 50 °C, increasing to 300 °C at a rate of 10 °C min-1, followed by a 10-min isothermal.
FAMEs were analyzed on a ThermoFinnegan single quadrupole TraceMS run in EI mode (electron energy 70 eV). The
oven program comprised a 2-min isothermal hold at 50 °C, increasing at 10 °C min-1 to 100°C and then ramping at 4 °C min-1
to 240 °C, ending with a 15-min isothermal. Samples run in full-scan mode had a scan range of m/z 50–650 and scan time of
0.6 s. The GC/MS was fitted with a polar column (VF23 MS, high cyano-modified cyanopropyl polysilphenylenesiloxane,
60 m x 0.32 mm i.d., 0.15 μm film thickness). Extracts analyzed in selected ion monitoring mode followed an identical
temperature program, and the MS was programmed to scan for ions m/z 105, 262, 290, 318, and 346.
GC/C/IRMS
GC-C-IRMS analyses were performed using an Agilent 6890 GC coupled to a Deltaplus XL via a Finnegan MAT GC
combustion III interface. The GC was fitted with a non-polar (CP-Sil CB, 100% dimethylpolysiloxane, 50 m x 0.32 i.d., 0.12
μm film thickness) column. Samples were introduced via a split/splitless injector in splitless mode. The temperature program
comprised a 2-min isothermal at 50 °C followed by an increase of 10 °C min-1 to 300 °C and a 10-min isothermal. The injector
temperature started at 70 °C and increased to 300 °C at a rate of 600 °C min-1 and was then held for 30 min. Faraday
cups were used to detect ions of m/z 44 (12C16O2), 45 (13C16O2 and 12C17O16O), and 46 (12C18O16O). Results were calibrated
against reference CO2 that was injected directly into the source 3x at the beginning and end of the run. All samples were run
in duplicate, and any runs with inacceptable reproducibility, standard values, peak shapes, or peak intensities were discarded
and repeated. External standards were run every 4 runs. The δ13C values were derived according to the following expression
and are relative to the international standard vPDB: δ13C‰ = ([R sample - R standard] / R standard) x 1000, where R = 13C/12C. The
δ13C values were corrected for the carbon atoms added during methylation using a mass balance equation (Rieley 1994).
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Appendix 2. Table showing the stable carbon isotope values and the presence of marine-derived biomarkers in sherds
containing significant quantities of lipid. APAAs: ω-(o-alkylphenyl)alkanoic acid; diOH FAs: dihydroxy fatty acid. D (x) =
detected (no.); “-” = not detected; n.a. = not analyzed.
Sherd House δ13C16:0‰ δ13C18:0‰ Δ13C‰ APAAs diOH FAs Isoprenoid FAs
JAR-1 7 -22.2 -21.8 0.4 C18-C22 n.a. n.a.
JAR-2 7 -22.2 -22.5 -0.2 C18-C22 n.a. n.a.
JAR-3 7 -22.2 -25.6 -3.1 C18-C22 n.a. n.a.
JAR-5 7 -27.5 -30.5 -3.0 C18 n.a. n.a.
JAR-6 7 -23.2 -25.3 -2.1 C18-C22 C18-C22 D (3)
JAR-7 7 -23.6 -24.7 -1.1 C18-C22 C18-C22 n.a.
JAR-8 7 -22.7 -22.4 0.3 C18-C22 C18-C22 n.a.
JAR-12 7 -26.2 -28.1 -1.9 - n.a. n.a.
JAR-13 7 -22.6 -24.3 -1.7 C18-C22 C18-C22 D (2)
JAR-14 5 -26.1 -32.7 -6.6 C18-C22 C18-C22 n.a.
JAR-16 7 -27.4 -30.1 -2.7 C18-C20 n.a. n.a.
JAR-17 7 -25.2 -29.0 -3.8 - n.a. n.a.
JAR-18 7 -21.6 -23.6 -2.0 C18-C22 n.a. n.a.
JAR-19 5 -23.8 -24.0 -0.2 C18-C22 C18-C22 -
JAR-21 5 -21.7 -21.4 -0.3 C18 n.a. n.a.
JAR-22 5 -24.1 -27.0 -2.9 C18-C22 C18-C22 D (1)
JAR-23 - -25.0 -26.3 -1.3 C16-C22 n.a. D (3)
JAR-24 - -26.2 -29.5 -3.3 C16-C22 n.a. D (1)
JAR-25 - -24.8 -27.5 -2.7 C16-C22 n.a. D (3)
JAR-14V 5 -24.7 -31.7 -7.0 C18-C22 n.a. -
JAR-15V 5 -22.2 -21.2 1.0 C18-C22 n.a. n.a.
JAR-22V 5 -25.6 -29.2 -3.6 C18-C22 n.a. n.a.
BN-17 LIA 1 -27.0 -30.2 -3.2 C18 - D (2)
BN-19 LIA 1 -26.9 -30.8 -3.9 C18 n.a -
BN-20 LIA 1 -27.1 -31.0 -3.9 - n.a -
BN-25 LIA 1 -27.6 -32.5 -4.8 C18 - -
BN-58 LIA 1 -28.3 -32.0 -3.7 - - n.a.
BN-62 LIA 1 -27.6 -32.5 -4.8 - n.a n.a.
BN-66 LIA 2 -27.4 -30.2 -2.9 C18 C18 n.a.
BN-66V LIA 2 -27.4 -30.2 -2.9 C18 n.a n.a.
BN-68 LIA 2 -26.8 -28.5 -1.6 - n.a n.a.
BN-69 LIA 2 -26.9 -31.0 -4.0 C18-C20 C18-C22 n.a.
BN-70 LIA 2 -26.8 -29.9 -3.1 C18-C20 C18 n.a.
BN-70V LIA 2 -26.8 -29.3 -2.5 C18 n.a n.a.
BN-71 LIA 2 -27.4 -31.7 -4.3 C18 C18 n.a.
BN-71V LIA 2 -26.9 -30.8 -3.8 C18 n.a n.a.
BN-72 LIA2 -28.1 -33.8 -5.8 - - n.a.
BN-74 LIA2 -26.6 -29.4 -2.8 C18-C20 C18 n.a.
BN-74V LIA2 -26.9 -29.8 -2.9 C18 n.a n.a.
BN-76 LIA2 -26.8 -29.3 -2.5 C18 C18 n.a.
BN-77 LIA2 -26.9 -29.9 -3.0 C18 C18 n.a.
BN-78V LIA2 -27.0 -29.7 -2.7 n.a n.a n.a.
BN-79 LIA2 -26.8 -30.0 -3.2 n.a n.a n.a.
BN-80 LIA2 -28.3 -32.5 -4.3 n.a - n.a.
BN-82 LIA2 -26.8 -29.0 -2.1 n.a n.a n.a.
BN-83 LIA2 -27.4 -30.6 -3.3 C18 C18-C22 n.a.
BN-84 LIA2 -28.0 -30.4 -2.4 - n.a n.a.
BN-86 LIA2 -26.8 -29.4 -2.5 - n.a n.a.
BN-87 LIA2 -26.8 -30.4 -3.6 C18-C20 C18 n.a.
BN-87V LIA2 -27.5 -30.7 -3.2 - n.a n.a.
BN-88 LIA2 -24.2 -25.4 -1.3 C18-C22 C18-C22 -
BN-88V LIA2 -25.1 -28.5 -3.4 - n.a n.a.
BN-89 LIA2 -26.8 -29.4 -2.5 C18 n.a n.a.
BN-35 E Norse -25.4 -31.4 -6.0 C18-C20 C18-C22 D (1)
BN-35V E Norse n.a n.a n.a C18-C20 n.a -
BN-90 E Norse -26.4 -29.9 -3.6 - n.a n.a.
Journal of the North Atlantic
L.J.E. Cramp, H.Whelton, N. Sharples, J. Mulville, and R.P. Evershed
2015 Special Volume 9
151
Sherd House δ13C16:0‰ δ13C18:0‰ Δ13C‰ APAAs diOH FAs Isoprenoid FAs
BN-91 E Norse -24.2 -27.9 -3.6 C18-C20 C18-C22 n.a.
BN-92 E Norse -27.6 -30.9 -3.4 - n.a n.a.
BN-93 E Norse -26.4 -30.9 -4.6 C18-C20 C18 n.a.
BN-94 E Norse -26.5 -28.7 -2.3 - n.a n.a.
BN-95 E Norse -26.6 -29.3 -2.7 C18 n.a n.a.
BN-96V E Norse -26.9 -31.1 -4.3 - n.a n.a.
BN-97 E Norse -27.4 -30.3 -2.9 - n.a n.a.
BN-99 E Norse -29.01 -30.5 -1.4 - n.a n.a.
BN-100 E Norse -28.9 -30.5 -1.6 - n.a n.a.
BN-101 E Norse -28.1 -32.2 -4.1 C18 n.a n.a.
BN-103 E Norse -28.0 -30.1 -2.1 - n.a n.a.
BN-104 E Norse -27.3 -30.9 -3.7 - n.a n.a.
BN-105 E Norse -26.2 -31.7 -5.4 C18-C22 C18-C22 -
BN-107 E Norse -25.9 -32.3 -6.4 - n.a n.a.
BN-108 E Norse -27.5 -32.7 -5.2 C18 n.a n.a.
BN-110 E Norse -25.4 -25.9 -0.5 C18-C20 C18 n.a.
BN-111V E Norse -26.8 -32.4 -5.6 C18 n.a n.a.
BN-28V M Norse n.a n.a n.a C18-C20 n.a D (3)
BN-29 M Norse -27.0 -31.3 -4.3 - n.a D (1)
BN-34 M Norse -26.3 -30.5 -4.2 C18 - D (1)
BN-34V M Norse -25.0 -28.7 -3.6 C18-C20 n.a D (1)
BN-45 M Norse n.a n.a n.a - n.a -
BN-115 M Norse -27.2 -31.0 -3.8 C18 n.a n.a.
BN-115V M Norse -27.8 -30.6 -2.8 - n.a n.a.
BN-117 M Norse -27.3 -30.1 -2.8 - n.a n.a.
BN-118 M Norse -26.7 -30.1 -3.4 C18 n.a n.a.
BN-121 M Norse -26.8 -32.0 -5.2 - n.a n.a.
BN-122 M Norse -28.0 -30.8 -2.8 - n.a n.a.
BN-123 M Norse -26.5 -31.8 -5.4 C18 n.a -
BN-123V M Norse -26.9 -31.4 -4.5 C18 n.a n.a.
BN-124 M Norse -27.2 -29.8 -2.6 C18 n.a n.a.
BN-124V M Norse -27.3 -29.7 -2.4 C18 n.a n.a.
BN-33 M-L Norse -27.6 -33.6 -6.0 - n.a -
BN-38 M-L Norse -25.7 -29.4 -3.7 C18-C20 C16-C18 D_(1)
BN-51 M-L Norse -26.4 -28.9 -2.5 - - -
BN-53 M-L Norse -26.4 -29.4 -3.0 C18-C20 n.a D (1)
BN-36 L Norse -27.3 -31.8 -4.5 C18-C20 C16-C22 -
BN-39 L Norse -27.6 -31.8 -4.2 C18-C20 - D (1)
BN-39V L Norse n.a n.a n.a - n.a n.a
BN-44 L Norse n.a n.a n.a - n.a -
BN-46 L Norse n.a n.a n.a - n.a -
BN-46V L Norse n.a n.a n.a - n.a n.a
BN-48 L Norse n.a n.a n.a - n.a -
BN-49 L Norse -27.2 -31.6 -4.5 C18 - -
BN-52 L Norse -26.5 -29.1 -2.6 C18-C20 n.a D (2)
BN-55 L Norse n.a n.a n.a C18-C20 C16-C20 n.a.
BN-125 L Norse -28.2 -30.7 -2.5 C18 n.a n.a.
BN-126 L Norse -28.2 -32.5 -4.4 C18 n.a n.a.
BN-126V L Norse -27.1 -32.4 -5.3 C18 n.a n.a.
BN-130 L Norse -28.3 -33.0 -4.8 - n.a n.a.
BN-131 L Norse -26.8 -30.8 -4.0 C18 n.a -
BN-8 Norse -27.6 -33.4 -5.8 - - D (1)
BN-8V Norse n.a n.a n.a C18 n.a -
BN-47 Norse -28.4 -33.6 -5.1 n.a n.a -