The Downpatrick gold hoards: a reconsideration based on chemical analysis

Of Things Gone but not Forgotten

Essays in archaeology for Joan Taylor

Edited by

J.R. Trigg

BAR International Series 2434 2012

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Of Things Gone but not Forgotten. Essays in archaeology for Joan Taylor

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The doWnPaTriCk hoards: an analyTiCal reConsideraTion

Richard Warner and Mary Cahill

Abstract: Many studies of Neolithic and Bronze Age artefacts and burial practices rely heavily on material excavated in the nineteenth century bThe history of the chemical analysis of Irish prehistoric gold, from the work of Hartmann in Stuttgart to the latest National Museum of Ireland project, is outlined. We re-iterate a problem of Hartmann’s silver values and show that simple XRF techniques measuring copper and silver can give extremely valuable, consistent results. It has been found that with these two elements it is possible to draw chronological, technological and even cultural conclusions.

A case study, using some data from the extensive database that has now been built up for Irish gold, addresses the problems of the date, origin and technology of the two hoards from Downpatrick, Co. Down. The Middle Bronze Age date of the neck-ring, and its origin in Iberia, are confirmed. It is shown, however, that most of the accompanying bracelets were made in Ireland in the Late Bronze Age, but coated with the earlier imported gold. The hoards are, therefore, of late Bronze Age date.

The analysis of Irish gold - some notes.

When Joan Taylor wrote her seminal book on insular Bronze Age goldwork (1980) she was able to take account of the first of the published reports and data-lists from Hartmann’s (1970; 1982) extensive programme of analysis of prehistoric gold artefacts from European museums, including most of the objects in the National Museum of Ireland. Hartmann had measured the silver, copper and tin present in the gold, and noted other elements present in trace amounts. Using these results, Taylor was able to put the study of prehistoric Irish and British goldwork on a firm, and scientific, footing, upon which she has built a much deserved reputation through a stream of further publications. The Downpatrick objects that form the main subject of this paper were sampled by her for Hartmann but, for some reason, were not analysed by him.

One of the authors (RW) also took a close interest in Hartmann’s gold results which, he believed, notwithstanding Taylor’s work had not received the detailed attention they deserved. In particular, he found Hartmann’s own statistical treatment of his results confusing and unconvincing. Hartmann had, for instance, discussed the basically three-dimensional data-set as if it were three univariate data-sets. Taylor had been persuaded to display the data in triangular graphs for her 1980 book, thus reducing the available information severely. Warner had attempted to treat the data in a trivariate manner, without a great deal of success, until he discovered that Hartmann’s silver values contained very little discriminatory information (for the reason given below). The simple expedient of ignoring the silver and plotting the tin and copper values as bivariate (2-D) graphs provided a breakthrough by clearly showing how the variation in these elements perfectly correlated (for

Ireland, at any rate) with the typological and chronological groupings.

Warner’s first publication of his analysis of Hartmann’s data in 1993 coincided with Joan Taylor’s decision to collect together a team of archaeologists, geologists and geo-metallurgists to explore the technology and possible sourcing of British and Irish prehistoric gold, through the use, in particular, of LA-ICP-MS.1 As part of this project the present authors2 undertook a programme of analysis (and re-analysis) of Irish prehistoric gold, both to confirm Hartmann’s results and to add to them. The objects were analysed on an energy-dispersive x-ray fluorescence (EDX or XRF) spectrometer in the National Museum of Ireland (NMI).3 This particular machine allowed rapid, non-damaging, carefully located measurements to be made on whole objects. Unfortunately, certain elements known to be of interest as potentially informative constituents of gold objects (mercury, tin, platinum and lead for instance) are not detectable at low levels, in the presence of significant levels of silver and gold, on this machine. In fact, in addition to the gold, only copper and silver can be satisfactorily measured. The inability to measure tin is particularly disappointing, for tin is an important techno-cultural discriminator (Warner 1993; 2004). We should point out that, while the percentages of the gold, copper and tin quoted and used in this paper are relative to the total (gold, silver, copper and tin) all the silver values given are, for reasons that will be explained elsewhere, the percentage of silver to silver plus gold.

1 This project (the Irish Prehistoric Gold Project) will be reported on elsewhere, but see Taylor et al 1997; Shell et al 1998; Watling et al 1999.2 With the assistance of Paul Mullarky and Lucia Harnett.3 A discussion of the procedures and a detailed report of the results of the NMI gold project will be published elsewhere.


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As part of the NMI project, many of Hartmann’s samples were re-measured. His copper values were found to be fairly reliable and, because he measured the tin in the same way, his results for that element, despite being near the limit of detection, may also be trusted. Nevertheless, his values for copper and tin should probably be regarded as semi-quantitative. His silver values, on the other hand, have proved to be quite unreliable and should not, without care, form part of any discussion on the content of ancient gold.4 Thus, the only non-gold element common to, and reliably

4 Hartmann used optical emission spectrometry for the copper and tin, but less reliable methodologies (for instance specific gravity) for the silver. See Warner (2004).

measured by, both the Hartmann and NMI projects is copper. Where one is obliged to use the Hartmann database, as is necessary with most European and British, and much Irish, ancient gold, its limitations with respect to silver must be recognised. We are satisfied that the values for silver and copper from the NMI project are reliable to within 10% and 20% respectively of the stated measure,5 and the gold to within 2%.6

5 When the copper is less than 1%, the reliability of its value is diminished considerably and must be considered to be qualitative only.6 Several project samples were also measured by RC Chapman on an electron microprobe (EPMA) in the Dept. of Earth Sciences in the University of Leeds; and the XRF values were confirmed (Chapman et al 2006: 910).

˝Fig. 1

Richard Warner and Mary Cahill: The Downpatrick Hoards

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Warner (2004) has discussed the archaeological ramifications of the Hartmann database with regard to Irish prehistoric gold, confirming that his analyses hold chronological, cultural and probably technological information in the copper and tin values (Fig.1.1; Warner 2004). He has suggested, on the basis of Hartmann’s data, that a small number of consistent gold alloys could account for the great majority of Irish objects of middle and late Bronze Age dates.7 Warner calls these alloys B-metal, F-metal and G-metal and he associates objects of middle Bronze Age date with the first two and of late Bronze Age date with the third.8 The definitions of the alloys are based on what he calls ‘core’ objects – in the case of B the core objects are the ornaments of the Derrinboy hoard and for F and G they are large and complex artefacts (4-flanged torcs and gorgets respectively). He shows that around these alloys certain other objects of comparable date, but often simpler and smaller, form more variable clouds (B*, F* and G*) whose class-means are close to the core-means but whose variances in both metals are greater. Although the core alloys are separate at a very significant statistical level, the clouds of subsidiary objects of one alloy occasionally overlap with those of another. This is especially true of those whose majority are associated with the G-metal, which can individually appear closer to the F-metal. In other words the placing of individual objects into an alloy-group might occasionally be misleading or ambiguous.

Now that the silver has been satisfactorily measured by the NMI project for many of the objects first analysed by Hartmann we find that the Irish alloy groups defined on copper and tin are almost as clearly separated on the basis of their copper and silver. This is clear from Figure 1.3 (which should be compared with Fig. 1.1) and is particularly important because the XRF technique now used by us (and widely by others) gives reliable measures for copper and silver, but not for tin. Although not so clearly separated, the three core types again form three independent groups, and again the other objects tend to cluster around the appropriate core-group. We shall refer temporarily to these alloys that are defined by silver and copper as B’, F’ and G’. We find that the members of each of these are generally the same as those of the B, F and G-metals. For instance, the change from B’-metal to F’-metal is characterised by the appearance of the four-flanged torcs as is the change from B to F. It can therefore be asserted that the change in copper, tin and silver – that is, both the technological and source changes – occurred at about the same times. It can also be allowed that the B, F and G metals are defined by all three elements, and can be identified if any two are measured,

7 This does not seem to be the case with British and Continental gold, which is far more variable. This matter will be discussed elsewhere.8 The B-metal belongs to Warner’s (2004) MBA 1, which is the earlier part of the Bishopsland phase (equivalent to the British Taunton phase). The F-metal (MBA2) comes from the later part of the Bishopsland phase (equivalent to the British Penard phase). The G-metal (LBA) is from the late Bronze Age Dowris-A phase (British Ewart Park). The date brackets are roughly 1400-1300, 1300-1150 and 950-800 respectively (Gerloff 2008, table 13.2). There appears to be no gold-working in the intermediate late Bronze Age Roscommon (=British Wilburton) phase.

and that the same metal-labels can be applied on both our tin-copper and silver-copper diagrams.9

The Downpatrick Hoards.

These two hoards were discovered in 1953 and 1956 and each was published by Proudfoot (1955; 1957) soon after their discovery. Both hoards were found on Cathedral Hill, Downpatrick (Co. Down) during the digging of graves in a new graveyard. They had, apparently, been buried in small pits and were some 18 metres apart. Excavations were undertaken close to the find-spot of hoard 1 in 1953 in order to ascertain both the context of that hoard, and the date of what appeared to be an extensive earthen enclosure surrounding the hill-top (Proudfoot 1954; 1955; Jope.1966: 98-9). The excavator claimed that an open settlement of late Bronze Age date had been followed by the construction of two consecutive and co-extensive ditched enclosures that were described as hill-forts. The earlier of these he also dated, on slender evidence, to the late Bronze Age. Unfortunately charcoal that had been found with hoard 2 has not survived, so a radiocarbon date cannot now be obtained. The same goes for any organic material from the ‘hill-fort’ excavations. The existence of a middle or late Bronze Age settlement seems, however, to be confirmed by ‘coarse’ pottery (which is not more closely datable) from the excavations and from elsewhere on the hill-top. However, the ‘hill-fort’ claim has since been disproved by subsequent excavations (Brannon 1986). The hill was, until a couple of centuries ago, almost surrounded by a tidal estuary and excavation on the lower slopes of the hill has reportedly uncovered evidence for significant Bronze Age metalworking activity (Halpin 2000).

Hoard 1 consisted of twelve objects – eleven bracelets and part of a decorated neck-ring10. In hoard 2 were four bracelets.11 The neck-ring (1.12) and one bracelet (1.11) are incomplete, having been intentionally cut.12 It is generally agreed that the Downpatrick neck-ring (1.12) is likely to be an import. It is a distinctive type that occurs in south-western Iberia (where it is most numerous), south-western France and Britain. In all these areas the neck-rings typically occur in hoards associated with expanded-terminal bracelets and other heavy gold ornaments.13 Downpatrick 1.12 is also highly decorated with the sort of geometric motifs typical of these Atlantic-coast ornaments. Although

9 This also applies to the alloy groups identified for the early Bronze Age (Warner 2004).10 A useful reconstruction of the neck-ring 1.12 is shown in Proudfoot 1955, 2, copied in Eogan 1994, 65.11 The components of hoards 1 and 2 are numbered 1 to 12 and 1 to 4 respectively by Proudfoot. These numbers are retained as the accession numbers AD1.1 – AD1.12 and AD2.1 – AD 2.4 in the Ulster Museum collection, and are used by Eogan (1983: 34-36, hoards 14 and 15; 1994, fig. 26 and passim). In Taylor (1980), appendix 1, the hoards 1 and 2 are called A and B, and the objects are numbered CoDn4-19 (see Table 1). The present location of bracelet 1.3 is unknown – if it came into the possession of the Ulster (then Belfast Municipal) Museum with the rest of hoard 1 in 1953 it was certainly missing when the hoard was drawn by the museum illustrator a short time later.12 Each represents about half of the original object.13 See Eogan (1994: 66-9), where there is a long discussion of the date and connections of the Iberian and other parallels.


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˝Fig. 2

˝Fig. 3


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it is accepted that the French and the Iberian ornaments form part of a connected tradition, there are small, but significant, differences – for instance, the Iberian neck-rings (called ‘Berzocana’ neck-rings) are always of circular section whereas the French and British examples (called ‘Marne’ neck-rings) are usually flattened-oval (Armbruster & Louboutin 2004: 138). The Downpatrick neck-ring is, on this measure, of the ‘Marne’ type (Taylor 1980: 58 and 66; Armbruster & Louboutin 2004: 138) - although its analysis suggests otherwise (see below). Although close parallels to Downpatrick 1.12 have been found in Britain these, also, are usually assumed to be imports from France. The date of the Berzocana/Marne neck-rings is extremely difficult to pin down. Eogan (1964: 281-2; 1983: 34; 1994: 65ff) places the two Downpatrick hoards, on the basis of the usually accepted date of the Continental hoards containing Berzocana-type neck-rings, into the later part of the middle Bronze Age (his Bishopsland phase). The association of neck-rings and a four-flanged torc in the Guînes (Pas-de-Calais) hoard certainly seems to confirm such a dating – as does the gold decoration on the Penard-phase spear-head from Pyotdykes in Scotland (Coles et al 1964). On the other hand Needham (2002) has, in the most recent statement of date known to us, placed the Milton Keynes (Buckinghamshire) hoard, with its Berzocana/Marne type neck-rings (and late Bronze Age pot), into the late Bronze Age. These assessments are nearly compatible if the ornaments date to around the twelfth century BC, but would differ by as much as 500 years at the opposite extremes of the phase-ranges.

All the bracelets from Downpatrick are penannular and all but one have (mostly slightly) expanded terminals. Some have a square (lozenge) cross-section, while most have circular (or oval) sections. The former are rare in Ireland,

but the latter are extremely common (these are Eogan’s (1994) ‘variety 10’). Proudfoot (1955: 2-4) claimed that all but one of the bracelets in hoard 1 had been cast to give square-sectioned bars, and that most were then hammer-finished to a round (or oval) section before being polished. The implication seems to be that the square-sectioned type, rather than being comparable to the non-expanded (but usually twisted) bar torcs of Eogan’s Bishopsland phase (middle Bronze Age) should be considered to be unfinished round-sectioned bracelets – an idea given support by the clearly ‘goldsmith’s property’ nature of hoard 1 (Proudfoot 1955: 12). Eogan (1964: 304) has stressed the importance of the bracelets with expanded terminals, to which class all but one of the Downpatrick bracelets belong, as characteristic of his late Bronze Age Dowris (A) phase. Indeed, all Irish associative evidence clearly places these bracelets into this period. Both the Hartmann and NMI programmes analysed a large number of bracelets, of all types, as well as other objects that are indisputably characteristic of the various phases of the middle and late Bronze Age. They show that Eogan’s conclusions of 1964 regarding the gold constituents of his Bronze Age divisions are mostly supported by the analytical evidence (Warner 2004). The only simple bracelets that can be shown to be middle Bronze Age, by association and analysis, have plain-terminals and the expanded-terminal bracelets can be shown to be late Bronze Age (Dowris-A phase). Typologically, associatively and analytically we find that the expanded-terminal bracelets form part of a wider ornament group that includes cup-ended bracelets and dress-fasteners.14 The majority of the Downpatrick bracelets (including those with lozenge sections), which in all respects match the bulk of Irish

14 There is absolutely no analytical (or archaeological) evidence for any internal chronology of development – slightly expanded to very expanded to cup-ended to dress-fastener.

Table 1. Properties of the Downpatrick ornaments.

no. (DnP) class section expanded detail weight (g)

Taylor no.(CoDn)

1.1 bracelet lozenge No 65.8 41.2 bracelet lozenge Slight 73.9 51.3 bracelet lozenge Slight Lost 48.8 61.4 bracelet lozenge Yes 66.7 71.5 bracelet lozenge Yes 45.8 81.6 bracelet circular Yes 67.4 91.7 bracelet circular Yes 43.4 101.8 bracelet circular Yes 56.9 111.9 bracelet circular Yes decorated 267.8 121.10 bracelet circular slight 19.8 131.11 bracelet circular yes, very half only 81.3 141.12 neck-ring flat-oval - decorated; half only 201 15 2.1 bracelet circular Yes 143.5 162.2 bracelet circular Yes 56.6 172.3 bracelet circular Yes 47.1 182.4 bracelet circular slight 62.9 19


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bracelets of that class, must be regarded, then, as being of late Bronze Age (Dowris-A) date.

Two of the bracelets seem rather different from the rest, and do not easily fit into the general description of Irish expanded-terminal bracelets. 1.9 is a large, thick-ringed bracelet with transverse grooves against each terminal, decorative hatched triangles next to these and a set of concentric circles on each terminal-end. A single bracelet of unknown provenance is the only Irish match we know of, and this lacks the distinctive terminal-end circles.15 This last feature is, however, found on a neck-ring of ‘Marne’ type from Ickleton, Cambridgeshire (Longworth 1972), which is a close parallel for the Downpatrick neck-ring and without a doubt has a similar date and origin. It is also found on one of three heavy, decorated bracelets, of probably the same origin, from Little Chart, Kent (Gordon 1965). We therefore believe that 1.9 is likely to be a companion import for 1.12. The cut bracelet 1.11 is also of a heavy form, with highly flared terminals, and is not easy to parallel among the Irish bracelets, which tend to be thinner and with less flared terminals.16 Bracelets of this shape are, however, found among the hoards containing Berzocana/Marne neck-rings – such as Balinghem, Pas-de-Calais (Armbruster & Louboutin 2004: fig. 1) and Milton Keynes, Buckinghamshire (Needham 2002). We have no hesitation in declaring 1.11 to be another object in the import group, and we draw attention to the fact that it had also been cut in half, presumably to provide gold.

Although, as we have shown, there is a wide range of uncertainty for the date of the imports in the hoard, there is, in our opinion, less uncertainty about the date of the Irish bracelets. These will not be earlier than the tenth century BC and it is quite clear to us that the date of the deposition of the hoard was within the Dowris (A) phase of the late Bronze Age.17 That the three imports (two halved) were there as raw material can hardly be doubted – and we note that the Irish-style bracelets from Downpatrick are all complete. If the imports are of late Bronze Age date, their

15 Armstrong (1933, no. 411); (NMI, W.194)16 These must be distinguished from the cup-ended bracelets, which have hollowed, highly flared terminals but are of the same general date.17 Both Taylor (1980) and Eogan (1964; 1983 & 1994) date all the Downpatrick objects, and their deposition, to the Bronze Age, despite the evidence of the bracelets, on the basis of their understanding of the date of the neck-ring.

presence is not unexpected given the occurrence of such objects in Britain and the fact that Downpatrick is on the shore of a protected but accessible harbour. However if, as seems more likely, the imports are of middle Bronze Age date their presence here in a late Bronze Age hoard is far more difficult to explain. The geographically closest neck-ring to Downpatrick, from Greysouthern in Cumbria, is also very similarly decorated and is a ‘Marne’ type (Needham & Richardson 1994). It had, like Downpatrick neck-ring 1.12, been severely butchered, although Needham and Richardson were unsure whether this was to provide gold or represented some kind of ritual ‘killing’. Our conclusions below, with regard to Downpatrick, will be seen to support the first suggestion.

Attention should be drawn to the weights of the Irish-style bracelets in the two hoards as they appear to follow a unit system – the unit being about 11gm (Figure 4).18 A unit of between 11 and 12gm has been recognised recently in both Irish and Welsh late Bronze Age bracelets and indicates that the bracelets have a weight-based ‘value’ (Gwilt et al 2005: 46-52). Most interestingly, in view of the connection described in this paper, the same unit is evident amongst objects belonging to the Iberian Berzocana group of gold ornaments and among British/Irish/French bar-torcs of the Tara/Yeovil type (Ruiz-Gálvez 2000: 271-2).19

The analyses.

The Downpatrick objects were not, apparently, analysed by Hartmann although samples were taken for his programme.20 Shell et al (1998), armed with LA-ICP-MS analyses of the Downpatrick objects made for the Irish Gold Project (above), found in the data a tight analytical group of four objects that were separated from the rest on the basis of a number of trace elements: these were the neck-ring 1.12 and the bracelets 1.2, 1.6 and 1.9. Noting that 1.12 was only half of a neck-ring he justifiably (at least, from the evidence he had) concluded that 1.2 and 1.6 had been made from the gold cut from 1.12, with 1.9 having a similar fingerprint perhaps because it was imported from the same milieu. Unfortunately, since the publication of this observation the project team have concluded that the LA-ICP-MS data were unreliable (Chapman et al 2006: 905-6) and, on this basis, the present authors believe that the conclusion of Shell et al was, in its detailed form, unjustified. However, their general conclusion is, as we shall see, valid – the neck-ring was indeed being used to modify, if not to make, the bracelets.

A substantial proportion of the Irish objects analysed for the NMI XRF project were subjected to two or more analyses on different parts of the artefact, and in the vast majority of

18 We have not determined that this is statistically significant.19 The imported bracelet 1.9, with a weight of 268gm, is equivalent to four ‘Aegean’ units. One Aegean unit is equal to six of the ‘11gm’ units (see Ruiz-Gálvez 2000: 270).20 In Taylor (1980: appendix 1) the ‘br’ number against each Downpatrick object refers to the sample collected by Taylor. The samples were not among a large number of surviving Irish and British Hartmann samples that were recovered recently from Freiberg University by Alison Sheridan and Mary Cahill.

Fig. 4


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Table 2. Equivalence and approximate dates of the later part of the Middle Bronze Age and the earlier part of the late Bronze Age (after Gerloff 2007).

Date N Eur Ireland Britain Atlantic SW1400-1300 II

MBA Bishopsland MBATaunton Middle BA

1300-1150 III PenardFinal BA1150-950 IV

LBARoscommon

LBAWilburton

950-800 V Dowris-A Ewart Park

Table 3. Analytical results from artefacts from Downpatrick hoards

NMI project

no. object no

analysis no.

sample description

Au%total

Cu%total

Ag%(Ag+Au)

1.1 108215 gouge 78.9 6.4 15.7216 surface 85.9 2.2 12.1217 surface 85.2 2.5 12.5

1.2 81

559 gouge 1 85.3 2.9 12.0560 gouge 2 88.2 1.8 10.1149 surface 86.8 2.0 11.3561 surface 87.1 2.4 10.7

1.3 - - - - -

1.4 109218 gouge 81.3 4.5 14.8219 surface 87.3 1.9 10.8


1.6 82 150 surface 84.7 2.8 12.8

1.7 105208 surface 85.8 2.1 12.3209 surface 87.9 1.4 10.8

1.8 83 151 surface 87.8 2.1 10.21.9 80 147 surface 87.4 2.0 10.7

1.10 106210 surface 87.9 2.1 10.1211 surface 84.2 3.5 12.6

1.11 78

139 cut 89.2 2.0 8.9140 cut 89.5 1.9 8.7141 cut 87.5 1.9 10.7142 gouge 84.6 3.2 12.6136 surface 82.5 3.3 14.7137 surface 84.3 3.1 13.0138 surface 83.3 3.7 13.5143 surface 81.7 4.3 14.6148 surface 84.8 2.8 12.7

1.12 79144 cut 87.2 1.3 11.5145 surface 85.6 1.9 12.7146 surface 88.0 2.0 10.1

2.1 307591 gouge 80.0 5.7 15.1592 surface 83.7 3.7 13.1


2.3 305588 gouge? 81.3 5.8 13.6587 surface 86.5 2.8 10.9

2.4 306589 gouge 79.8 5.9 15.1590 surface 88.9 1.7 9.5


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these cases the differences are small and are best explained as due to minor variations in the metal content or inherent errors in the measurement process. In almost all cases, the metal could be described as homogeneous. This is certainly not the case for the Downpatrick ornaments, two-thirds of which (10) show a significant variation between the analysed points (Figure 5). On the Downpatrick objects, we analysed both the surface and (when possible) the bottom of the gouge from which a sample had been removed for Hartmann – hoping that the two spots, differing in depth, would give us information about surface effects. On the two

ornaments (1.12 and 1.11) which had been halved prior to burial, we also analysed the cut face for information about the deep body, to test for homogeneity.

We shall, in this section, use the term ‘body’ to refer to the deep interior, whose analytical values we know directly only for objects 1.11 and 1.12 from their cut sections. We shall use the term ‘sub-surface’ to refer to the shallow interior exposed by the gouge, which we assume gives some information about the body proper. The plots (Figures 3 and

Fig. 5


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4) for the 15 ornaments show the repeat analyses, and on each plot we show also the mean of all the ‘body’ analyses21 and the mean of all Irish late Bronze Age (LBA) objects so-far analysed by us (G/G* alloy)22 – primarily to allow the patterns to be fixed and compared visually. For each of these means we also show the 95% probability area (two standard deviations) of the analyses from which they were calculated. We shall refer to these areas as ‘alloy-A’ and ‘alloy-B’, and the small area between, but outside them, as ‘AB’ – without implying that this represents a physical mixture of the two.

A marked, and consistent, pattern in the variations is evident, which is completely at odds with any notion of post-deposition surface effects.23 One object (1.12) corresponds to alloy-A both in body and in surface – this is the neck-ring, and is the sole provable member of the group we are calling group-1. The three analyses – two of the surface and one of the body – are very close and imply a homogeneous metal. Six of the bracelets (1.1, 1.4, 1.5, 2.2, 2.3, 2.4) have surfaces that correspond to the alloy-A, but have sub-surfaces that correspond to alloy-B. We shall call these group-2, and we have no doubt that these represent objects whose bodies are made of alloy-B, but are surfaced with alloy-A. A further bracelet (1.2) appears to give a mixed reading in one sub-surface analysis. This might mean that lozenge-sectioned 1.2 actually belongs to group 1 – but we are inclined to interpret this as indicating a thicker surface than the others, so that the body-alloy (B) is only just registering. In other words this is probably mixed radiation – and with some trepidation we place this

21 Silver 10.0%, copper 1.8%, gold 88.4%.22 Silver 13.7%, copper 5.5%, gold 81.7%. These means were obtained from 87 objects of certain late Bronze Age date, and do not include those from Downpatrick.23 Hook & Needham (1989: 19) show that burial can result in a slight surface depletion of both silver and copper. The very large difference in the copper levels in some, but not all, of the Downpatrick bracelets cannot, in our opinion, have a natural explanation.

Table 4. Simplification of the analytical data, and the groups; number in bracket is the number of analyses that have this reading, when greater than 1; alloy in brackets denotes an inference explained in the text.

Surface sub-surface body group1.12 A(2) A 11.1 A, AB B (B) 21.4 A B (B) 21.5 A(2) B (B) 22.2 A(2) B (B) 22.3 A B (B) 22.4 A B (B) 21.2 A(2) A, AB (B) 2?1.7 A(2) ? ?1.8 A ? ?1.9 A ? ?1.10 A, B (B?) ?1.6 AB (B?) ?2.1 B B (B) 2b1.11 B(4), AB AB A(3) 1b

also into group-2. These two groups account for 8 of our 15 ornaments, covering both hoards 1 and 2 – of these, seven are in group-2. For five ornaments (1.6 to 1.10) no gouges were looked at - only the surfaces were analysed. The surfaces of three of these (1.7, 1.8, 1.9) were certainly of alloy-A and they could belong to either group-1 or -2. We suggest that their membership of group 2 is the most sensible conclusion, given their typologies and the record so far. Another (1.6) gave a ‘mixed’ reading, and we are again confident to interpret this as a mixed radiation from a thin alloy-A surface, and to declare that it is consistent with group 2 membership. 1.10 had a surface that gave one reading of alloy-A and another of alloy-B. That the surface is discontinuous, and both metals are present at the surface, seems the probable explanation, which makes it consistent with group-2. Bracelet 2.1 has a surface and sub-surface of alloy-B. In this case we interpret the bracelet as being un-surfaced alloy-B, and place it into a group-2b. Bracelet 1.11 is the most difficult to explain. It had been halved and the three measurements of its body all show that it is made of alloy-A (as 1.12). On the other hand, four of the five surface measures show that it is surfaced with alloy-B. That this is only the surface is shown by the mixed-radiation (AB) results of one surface and one sub-surface analysis. This becomes the only member of a group-1b.

Had we not had the gouges to analyse, but had simply analysed the surfaces, we would have concluded that all but two of the bracelets consisted completely of the alloy-A. As we shall see below this would have persuaded us either to date most of the objects to the middle Bronze Age, or to conclude that they were of late Bronze Age date, but made of an earlier metal. Although none of the non-group-1/1b objects provided us with a true deep-body analysis, we are satisfied, from the consistency of the sub-surface results, that the bodies of those in group-2 were indeed of the late Bronze Age alloy–B (equivalent to G/G*-metal), but that they had been coated with alloy-A. This confirms


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our typological conclusion that the group 2 bracelets are certainly of late Bronze Age date. This conclusion includes 1.1 – which is unexpanded (we may suppose that its terminals had not yet been hammered up24) – and all but one of the bracelets with lozenge-shaped sections. We have shown that the five normal bracelets for which we have no sub-surface analyses are not incompatible with group 2. As for 1.11 – this is certainly made of alloy-A and was surfaced with alloy-B. It is, in other words, the opposite of group 2. We have suggested above, from typological considerations, that the imports consisted of neck-ring 1.12 and the bracelets 1.9 and 1.11. The analyses tell us that

24 Proudfoot (1955: 5) claims the expansions were achieved by hammering.

1.12 was completely alloy-A. For 1.9 we had no analysis other than surface, which was alloy-A - it is therefore quite possible that the whole bracelet is alloy-A. We found that bracelet 1.11 was also made of alloy-A but had been coated with B. We conclude that bracelet 1.11 was coated with late Bronze Age metal to test the surfacing technology, and that it was then cannibalised for its alloy-A body. We would add that such an interpretation would explain the presence of mixed material (AB) on some of the other bracelets.

Discussion

We have concluded that many, possibly most, of the Downpatrick late Bronze Age (alloy-B = G/G*-metal)

Fig. 6


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bracelets were surfaced with gold derived from the imported, and apparently considerably older, neck-ring 1.12, the bracelet 1.11 and perhaps other ornaments from the same milieu. One bracelet (2.1) was left un-surfaced. The LBA alloy-B has about 82% gold, 13% silver and 5% copper, whereas the values for alloy-A are, respectively, about 88%, 10% and 2%. It might be felt that the purer gold surface was required either for visual preference or to enhance the apparent value of the bracelets, except that the lower copper and silver cancel each other out and there is actually very little visual difference. Perhaps there was a religious reason, the imported gold imparting an extra exotic value to the bracelets. We point out that the lozenge-sectioned bracelets were also made of alloy B and have been coated with alloy-A, which appears to weaken the supposition that they were unfinished.

There is an interesting question as to whether the introduction of the low-copper gold represented by the alloy-A at Downpatrick can be recognised in other objects of the Irish late Bronze Age. First we discuss the re-use of coated bracelets. If we are correct that the surface ‘wash’ of alloy-A is extremely thin, as indicated by most of the gouge results (let us say, about 1/10th of a millimetre), the re-melting of a composite bracelet would have a minimal analytical effect – the new mix would be indistinguishable from LBA gold. If, on the other hand the surface was one millimetre thick the mix would have mid-point values. The 2sd area shown on the charts here makes it clear that even mid-point values can lie within the LBA scatter, and

Fig. 7

therefore be indistinguishable from LBA gold. We conclude that such objects would be difficult to identify. On the other hand, the coating of other objects with the alloy-A (or the making of other objects with alloy-A) would certainly be obvious were those other objects of late Bronze Age date typologically. In this case, however, we would find it difficult to decide whether the results were due to imported alloy-A or the B/B*-metal of Irish MBA1, which is very similar.

An inspection of the database of the NMI project has found very few late Bronze Age objects whose analyses suggest the use of alloy-A (Fig.7.2). Two bracelets (one with expanded terminals of Irish type, the other of a ‘recurved’ British form) found at Ballymaclode (Co. Waterford) give closely similar intermediate surface values, and may well have been made of an intermediate mix. In a collection of gold balls from Tumna (Co. Roscommon) (Cahill 2004) five are of normal LBA G/G* gold (alloy-B), but one gives a surface value close to that of alloy-A. A small hoard of ornaments from a late Bronze Age site at Killymoon (Co. Tyrone) (Hurl 1995) is particularly interesting. Both ornaments are characteristically late Bronze Age, and all the analyses are surface. The sleeve-fastener gives three very close results corresponding to an intermediate alloy, while its accompanying cup-ended bracelet has one analysis showing intermediate alloy and three showing results compatible with alloy-A. An unprovenanced gorget shows two results matching the Killymoon sleeve-fastener, while another gorget, from Co. Clare, has three values showing


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both intermediate and alloy-A-compatible metal to be present. These examples are an insignificant proportion of the late Bronze Age objects that have been analysed, and cannot be regarded as a significant exception to the otherwise sound rule that most Irish objects show analytical results consistent with their date and culture.

What appears to have been a large bracelet, decorated in Berzocana-style, is recorded (with a woodcut representation) as having been found in Creeveroe (Co. Armagh) in about 1770 (Stuart 1819: 512 and pl. 2; Warner 1986: find no. 36). The object has not since been reported, and was probably melted down. The find-spot is very close to the hill-fort of Haughey’s Fort, Co. Armagh (Mallory 1995), from which a large number of tiny fragments of gold were recovered showing the existence of a gold-working site (Mallory 1991: 20; 1995: 80). The date of Haughey’s Fort is late Bronze Age, probably the Roscommon phase. The data from the analyses of the fragments form a scatter running between some unknown source of gold with about 13% silver and 1.8% copper, and the LBA mean – it is very similar to the Downpatrick scatter. The unknown source of gold is not very far removed from the imported alloy-A or the native B/B*, but is slightly richer than both in silver. Native artefacts with this sort of metal are difficult to find

in our database, and we feel that the source might have been either a portion of the lost Creeveroe ornament or a companion.25

In Fig. 8.1 we show alloy-A compared with the Irish gold groups, and the Ickleton and Greysouthern neck-rings (to which Downpatrick 1.12 has been compared).26 It will be seen that the alloy-A is not far removed from the B/B* cluster and, were the objects Irish, we would not have hesitated to place them into the middle Bronze Age (Warner’s metal-group MBA1). The two British neck-rings, on the other hand, with higher silver and copper, lie very close together and within the F/F*-metal of the Irish middle Bronze Age (but of Warner’s slightly later MBA2). They are also analytically indistinguishable from a flange-twisted torc from Burton, North Wales, from a hoard of bronzes and gold which is certainly of Penard-phase date (the same date as our F/F*-metal).27 Notwithstanding an observation of Hartmann’s - that the changes in the gold composition throughout the Bronze Age are to a large extent paralleled in the different European gold-using regions (1979 passim) –

25 This Haughey’s Fort gold will be discussed more fully elsewhere. 26 These are either from the NMI project database or were done on comparable equipment.27 For the hoard, Gwilt et al 2007; for the analysis Gwilt personal information.

Fig. 8


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we might ponder the possibility that these British (and Irish) neck-rings are not imports but are locally made versions of the Continental objects, as Needham and Richardson (1994: 18) have tentatively suggested. Unfortunately, as far as we are aware, the only available analyses of the Continental Berzocana/Marne objects are Hartmann’s, and we are unaware of any reconsideration of his analytical results for Continental ornaments comparable to that of Warner (2004). In Fig. 8.2 we show Hartmann’s copper-tin measurements for a number of Iberian Berzocana-group objects as well as of a Marne-style neck-ring from Kerviltré, Morbihan.28 The Kerviltré neck-ring, however, is more comparable to Irish G/G*-metal, which, if it were Irish, would indicate a late Bronze Age date. Notwithstanding our comments on the unreliability of Hartmann’s silver values, we believe that a fairly reliable mean value for the silver in the ‘Berzocana-type’ gold can be derived from the Hartmann data – the values for the silver and copper, 13% and 1.7% compare very well with the 11.4% and 1.7% for the Downpatrick neck-ring 1.12. We are therefore inclined towards an Iberian rather than a French or British origin for Downpatrick 1.12. We also suggest that our analyses, coupled with those of other neck-rings discussed above, appear to confirm the middle Bronze Age rather than the late Bronze Age as the likely date of the neck-ring and the other imports and, by extension, of the Berzocana/Marne traditions.

Conclusion

The Irish style bracelets in the two Downpatrick hoards were made of typical Irish late Bronze Age metal. They were, however, surfaced with gold derived from ornaments, three of which were found in one of the hoards, probably imported from Iberia in the middle Bronze Age. The date of the bracelets, and of the deposition of the hoard, is, without a shadow of a doubt, the Dowris-A phase of the late Bronze Age. But the imports (neck-rings and two bracelets) seem almost certain to be contemporary with the Irish Bishopsland phase. The latest chronological assessment would place this phase between the 14th and mid-12th centuries BC and the Dowris-A phase between the mid-10th century and about 800 (Gerloff 2007: table 13.2). At least two, and possibly as many as six, centuries separate these phases and an explanation must be offered. Three possible explanations come to mind: the imported objects were recovered from an earlier hoard; the objects had been preserved by a succession of goldsmiths; the objects had been preserved as valuable personal items. We strongly favour the last,29 while remaining cognisant of the

28 The Kerviltré hoard is known more widely as the Saint-Jean-Trolimon hoard. The metal of the bar-torcs and other objects from the Iberian Bodonal hoard (Almagro Gorbea 1974) are, judging by Hartmann’s analyses, virtually identical to our Irish B-metal, with which they are roughly contemporary, but also match the metal of the Berzocana neck-rings rather well.29 We draw attention to such other hoards as Pyotdykes (Angus; Coles et al 1964) where a middle Bronze Age basal-looped spearhead, decorated with gold leaf whose motifs were derived from the Berzocana/Marne style discussed above and whose analysis (Hartmann 1980, au4557) firmly places it into the middle Bronze Age, was found with two swords of late Bronze Age (Ewart Park) type.

widely varying opinions on the date of these neck-rings. If Needham (2002) is correct in his late dating of the neck-rings there is no inconsistency in the chronological make-up of the Downpatrick hoards, but for the reasons given above we are inclined to favour the earlier date for the imports.

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The Downpatrick gold hoards: a reconsideration based on chemical analysis

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