THE TREASURE OF GUARRAZAR: TRACING THE GOLD SUPPLIES IN THE VISIGOTHIC IBERIAN PENINSULA*

Archaeometry

49

, 1 (2007) 53 –74. Printed in Singapore

*Received 1 September 2004; accepted 3 May 2006© University of Oxford, 2007

Blackwell Publishing LtdOxford, UKARCHArchaeometry0003-813X© University of Oxford, 2007XXX 2007491

ORIGINAL ARTICLE

The treasure of GuarrazarM. F. Guerra, T. Calligaro and A. Perea

THE TREASURE OF GUARRAZAR: TRACING THE GOLD SUPPLIES IN THE VISIGOTHIC IBERIAN PENINSULA*

M. F. GUERRA and T. CALLIGARO

Centre de Recherche et de Restauration des Musées de France, UMR 171 CNRS, Palais du Louvre—Porte des Lions, 14 quai François Mitterrand, 75001 Paris, France

and A. PEREA

Departamento de Prehistoria, Instituto de Historia, CSIC, Calle Serrano 13, 28001 Madrid, Spain

The treasure of Guarrazar, found in the 19th century in Spain, is the most importantillustration of the high level of Visigothic jewellery in the Iberian Peninsula. The votivecrowns and crosses of this treasure are an arrangement of pierced gold in a Byzantine–Germanic style, decorated with emeralds, garnets, sapphires and other materials. In orderto establish the provenance of the gold, we analysed a group of 46 minute samples from themost important pieces kept in Spain for major and trace elements. The combination of PIXEand PIGE with an external 3 MeV proton

µ

-beam was used to analyse the samples.Considering the gold sources cited by Pliny the Elder and the composition of contemporaryVisigothic coins, we suggest the exploitation of south Iberian mines. Using the same set-up,we complemented these results with the analysis of 11 emeralds inlaid in items from theGuarrazar jewellery that is kept in France. We suggest the use of European sources unknownto the Romans for these gemstones.

KEYWORDS:

GOLD, GEMS, PROVENANCE, IBA, VISIGOTH, GUARRAZAR

*Received 1 September 2004; accepted 3 May 2006© University of Oxford, 2007

THE TREASURE OF GUARRAZAR

The treasure of Guarrazar was found in Spain at the end of the 19th century in the countrysideof Guadamur, near Toledo. In 1858, a rainwash uncovered some ancient tombs and removedone of the sealing slabs of two hiding places, lined with concrete, where this exceptional hoardwas preserved (Perea 2001). This treasure is one of the most important remains of jewelleryfrom the beginning of the Christian period preserved in Europe, and presents some of the finestpieces manufactured by Germanic goldsmiths. It consists of a group of crowns and crossesinlaid with polychrome gemstones, as well as hanging chains and other objects in the Germanicand Byzantine traditions. These crowns and crosses are made from a combination of sapphires,garnets, mother-of-pearl, emeralds and glass beads, set in heavy pierced gold bands in asophisticated style that suggests trade links with the Byzantine world. The hanging chainssuggest a ritual use as liturgical artefacts and votive offerings of Visigoth kings, nobles andbishops. This votive jewellery was certainly displayed during the seventh century AD in achurch in Toledo, the capital of the Visigothic kingdom.

Much of the jewellery found in the hiding places of Guarrazar was sold and melted down.Despite the loss in 1921 of some of the major pieces of the treasure, when the crown of KingSuintila (

ad

621–31) was stolen in Madrid, together with two other objects, the treasure of

54

M. F. Guerra, T. Calligaro and A. Perea

© University of Oxford, 2007,

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Guarrazar still includes the crown of devotion of King Recceswinth (

ad

652–72), as well asother masterpieces that show the high level of the Visigothic craftsmanship. The jewellery thatsurvived—10 crowns, nine crosses, 16 pendants, and chains and parts of different objects—isshared at present by the Museo Arqueologico National (National Archaeological Museum) andthe Museum of the Royal Palace, both in Madrid, as well as by the Musée national du MoyenAge (Museum of the Middle Ages) in Paris.

No document cites the burial of the Guarrazar treasure, which means that the event cannotbe precisely dated. However, the most likely reason for this burial is the arrival of theArabs in the Iberian Peninsula in the beginning of the eighth century

ad

. It was in

ad

711 thatthe army of the last Visigothic king, Roderick (

ad

710–11), was defeated by the Moors inGuadalete. Two years later, most of Iberia was submitted to Islam and renamed Al-Andaluz.This Islamic domination began to decline in 1212, with the defeat of the Almohads in thebattle of Navas de Tolosa. It finally disappeared in 1492 with the fall of Granada, the last Arabstronghold in the Iberian Peninsula. Over such a long period, the burial of that jewellery fellinto oblivion.

Despite the important contribution of the treasure of Guarrazar to our knowledge of theVisigothic goldsmiths’ techniques, this treasure was not studied in depth until the publicationof a book in 2001, in which studies by several scholars on the quality of the gold and theidentification of the gemstones were published (Perea 2001). Some of the analyses werecarried out in one of the European programmes of the COST G8 action ‘Non-DestructiveAnalysis and Testing of Museum Objects’ at the LARN (Belgium) and the C2RMF (France).The manufacturing techniques used by the craftsmen were presented and discussed in Perea(2001). Nevertheless, the provenance of the gold was not investigated.

Under the Romans, the Iberian Peninsula owned important gold-mining resources (see, e.g.,Shepherd 1993; Lehrberger 1995), the greater part of which were described by Pliny the Elderin his

Natural history

and cited by Strabo in his

Geography

. However, it is accepted thatthese resources were already exhausted by the time of the Visigothic era. On the other hand,the Guarrazar jewellery style suggests trade links with the eastern Mediterranean and theVisigoth–Roman alliance suggests commercial exchanges with the western Mediterranean.

The aim of this paper is to identify the origin of the gold and to localize the gold sourcesexploited by the Iberian Visigothic goldsmiths. For this purpose, the trace element contents offive crosses and five crowns from the treasure of Guarrazar, kept in Spain, were measured.These results were compared to the trace element contents of contemporary Visigothic goldcoins. The trace element compositions of monetary Byzantine and Roman gold, published, byMorrisson

et al

. (1985) and Poirier (1983), respectively, was also taken into account. In orderto approach, in a more extensive way, the circulation of the raw materials used by the Visigothicjewellers, the identification and provenance of the gemstones inlaid in three crowns and twocrosses kept at the Musée national du Moyen Age in Paris were also considered (see Fig. 1).

THE ANALYTICAL TECHNIQUES

The provenance of the different materials used to fabricate the Guarrazar jewellery can beinferred from the concentration of the most representative trace elements in each material(Guerra and Calligaro 2003). To carry out trace element analysis on the gold and the gem-stones of Guarrazar, we used accelerator-based techniques. In this section we present the mainfeatures of the ion beam methods developed around the AGLAE accelerator, installed at thePalais du Louvre in Paris.

The treasure of Guarrazar

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Elemental analysis was performed by the combination of two ion micro-beam techniques:particle-induced X-ray emission (PIXE) and particle-induced

γ

-ray emission (PIGE). Theexternal 3-MeV proton beam of the AGLAE accelerator is brought in air through a Si

3

N

4

foil andfocused to a diameter of 30

µ

m. When impinging on the sample, protons produce the emissionof X-rays and

γ

-rays. In the case of PIXE, two Si(Li) detectors are used to collect the X-raysemitted by the sample (Calligaro

et al

. 2000b; Dran

et al

. 2000). Selective filters are chosenaccording to the base matrices and the elements to be determined. Quantification is performedwith the GUPIX program (Maxwell

et al

. 1988). This program evaluates without standardsthe elemental concentration of the sample by comparing the measured and evaluated PIXEspectra. In the case of PIGE, the

γ

-ray lines emitted by a few elements are measuredsimultaneously with PIXE by using a 30% efficiency HPGe detector placed at 45

°

to thebeam. Quantification is performed by direct comparison with standards. Elemental maps wereobtained for both techniques by mechanically scanning the sample under the fixed beam.

The main experimental difficulties of this work come from (a) the small size of the goldsamples, which must be analysed non-destructively, and (b) the gemstones, which cannot bedismounted. A

µ

-beam was used to carry out analysis on the inlaid gems as well as on theavailable unobtrusive 100–200

µ

m diameter gold samples mounted in resin.

The gold alloys

In the case of gold, one of the Si(Li) detectors is used to measure major elements, while theother, with a 75

µ

m Cu filter to absorb the Au lines, provides trace elements. The backgroundproduced by nuclear reactions in the sample constrains the limits of detection. With a 30–40

µ

C integrated charge, the limits of detection reach 10–90 ppm for elements with atomicnumber between 20 and 60 and 100–300 ppm for elements with atomic number higher than 75

Figure 1 The PIXE–PIGE µ-beam set-up at the AGLAE accelerator (C2RMF, Palais du Louvre in Paris) during the analysis of one of the crowns of the Guarrazar treasure.

https://www.researchgate.net/publication/222988215_Development_of_an_External_Beam_Nuclear_Microprobe_on_the_AGLAE_Facility_of_the_Louvre_Museum?el=1_x_8&enrichId=rgreq-3268c19b-0156-4f7f-a607-ff45a6ba3032&enrichSource=Y292ZXJQYWdlOzIyOTYyNzMwODtBUzoxMDE5OTM2MTU5ODY2OTdAMTQwMTMyODU4MTkxMQ==

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(Guerra and Calligaro 2004). The PIXE method probes the sample at a depth ranging between5 and 20

µ

m, and the possible elimination of copper from the surface by oxidation may biasthe final result. To overcome this problem, the

γ

-ray lines emitted by copper, silver and gold(at 152, 309 and 279 keV, respectively) are simultaneously measured by PIGE. DifferentAu–Ag–Cu alloy standards from CLAL-France (Comptoir Lyon-Allemand) are used to quantifythe

γ

-ray measurements.Figure 2 shows the good agreement for modern and ancient gold samples between PIGE

and other less surface sensitive techniques (Guerra 2004). The concentrations obtained byPIGE match the concentrations obtained either by 12 MeV proton activation analysis (PAA,which analyses a layer of about 200

µ

m in a gold alloy, the largest contribution neverthelesscoming from the first 50

µ

m) or by bulk fast neutron activation analysis (FNAA). A descriptionof the PAA and FNAA nuclear activation techniques can be found in, for example, Guerra andBarrandon (1998). Figure 3 illustrates, for the Guarrazar samples, the good agreement obtainedby PIXE and PIGE for copper, silver and gold contents.

Figure 2 Gold contents obtained by different techniques—near-surface PIXE, deeper PIGE, semi-global PAA and global FNAA—for a group of ancient samples, modern standards and nuggets.

Figure 3 The gold, silver and copper contents in per cent obtained by PIXE and PIGE for the Guarrazar samples.

https://www.researchgate.net/publication/239346603_Fingerprinting_ancient_gold_with_proton_beams_of_different_energies?el=1_x_8&enrichId=rgreq-3268c19b-0156-4f7f-a607-ff45a6ba3032&enrichSource=Y292ZXJQYWdlOzIyOTYyNzMwODtBUzoxMDE5OTM2MTU5ODY2OTdAMTQwMTMyODU4MTkxMQ==



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The copper absorber applied to the second Si(Li) detector absorbs the Au L-lines, whichimproves the detection limits of trace elements. Figure 4 compares the spectra obtained withand without absorbers. In the first case, either a 75

µ

m copper filter or a 75

µ

m zinc filter wasconsidered. The use of a copper filter instead of the classical PIXE set-up improves the traceelements detection limits by a factor of between 10 and 100. Figure 5 compares the palladium,tin and antimony contents obtained by filtered PIXE and PAA for a small set of ancient goldsamples. As expected, if we exclude concentrations out of the range of the detection limits(under 10 ppm), good agreement is observed for the two techniques.

Figure 4 The spectra obtained for the same gold sample (93% Au, 3% Ag, 4% Cu and 200 ppm Pd) by classical and filtered PIXE. The use of a 75 µm Cu filter improves the detection limits for elements such as Pd.

Figure 5 The palladium, antimony and tin contents obtained by near-surface PIXE and semi-global PAA for a group of ancient gold samples. Concentrations under 10 ppm are inferior to optimized detection limits.

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When the detection limits cannot be improved by the use of a selective absorber, we can incertain situations take advantage of an appropriate PIXE–XRF set-up (Guerra 2005). Thistechnique measures elements whose X-ray lines are situated below those of the major constituentof the sample. In the case of gold, by using an arsenic primary target, we can excite platinum(atomic number 78) without exciting gold (atomic number 79). If PIXE with a 75

µ

m Znselective filter shows a detection limit of 1000 ppm for platinum in gold, PIXE–XRF canimprove this detection limit to about 80 ppm.

We must, however, keep in mind that in the case of gold alloys, accelerator-based techniquespresent detection limits that differ by a factor of 100 to 1000 compared with those obtained byICP mass spectrometry (Gondonneau and Guerra 1999; Guerra 2004). In fact, ICP–MS ismore appropriate for the measurement of ultra-trace elements in many different matrices, itsdisadvantage being its slight destructiveness, by requiring the dissolution of a 2 mg sample inthe case of gold (Gondonneau

et al

. 2001).All of the techniques mentioned have advantages and disadvantages. While mass spectrometry

has better detection limits than IBA techniques, it requires the destruction of a small sample.For example, in the case of nuclear activation analysis, which induces radioactivity in thesample, neutrons cannot be used to quantify minor and trace elements and protons cannot beused to carry out multi-elemental point analysis on the samples. The tiny samples taken fromthe crowns and crosses of Guarrazar are too precious to be destroyed and too small to beanalysed by PIXE–XRF. In this case, the combination of PIXE and PIGE with an external

µ

-beam represents a good compromise.

The gemstones: emeralds and garnets

The provenance of gemstones may sometimes be assessed by the study of the nature, morphologyand phase identification of their microscopic mineral inclusions. However, ancient species arenot clear enough to allow their optical examination. For this reason, chemical characterizationof the major constituents allows us to identify the gems, while trace elements can sometimesfingerprint their origin.

Several analytical techniques have been applied to characterize either garnets (XRF, Greiff1998; SEM–EDX, Quast and Schüssler 2000) or emeralds (XRF, Schwartz 1991; SEM–EDX,Aurisicchio

et al

. 1988; SIMS, Giuliani 1998; ICP–MS, Peucat

et al

. 1999). However, accelerator-based techniques allowing non-destructive analysis without preparation and simultaneousdetermination of trace and major elements are still an attractive option (Xin Pei

et al

. 1993;Farges 1998; Yu

et al

. 2000; Calligaro

et al

. 2001b).Emeralds belong to the beryl family. Their colour is due to the replacement in the beryl

structure—chemically described by Be

3

Al

2

(SiO

3

)

6

—of Al by transition elements such as Cr, Vand Fe. In this work, emeralds were analysed by the same combination of PIXE and PIGE thatwas used for the gold alloys. The specific advantage of PIGE is the measurement of beryllium,lithium and fluorine, highly significant constituents of emeralds that are out of reach withX-ray based methods. In the PIXE set-up, a first Si(Li) detector without a filter in a heliumflow measures the X-rays emitted by elements with atomic numbers ranging from 10 to 30.A second Si(Li) detector, with a 50

µ

m Al absorber, allows the determination of trace elementswith atomic numbers ranging from 20 to 92. The HPGe detector simultaneously records thegamma rays emitted by the sample. Beryllium, lithium and fluorine are quantified by usingthe following calibrated standards: NIST 1412 for lithium, beryllium oxide for beryllium andthe MA-N geological standard for fluorine.

https://www.researchgate.net/publication/227078083_Oxygen_isotope_systematic_of_emerald_relevance_of_its_origin_and_geological_significance?el=1_x_8&enrichId=rgreq-3268c19b-0156-4f7f-a607-ff45a6ba3032&enrichSource=Y292ZXJQYWdlOzIyOTYyNzMwODtBUzoxMDE5OTM2MTU5ODY2OTdAMTQwMTMyODU4MTkxMQ==



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Figure 6 shows the spectra obtained by PIXE and PIGE on a reference emerald extractedfrom the Urals mines. The detection limits for these samples are in the ppm level (Calligaro

et al

. 2000a).Garnets, widely used during the early Middle Ages, belong to a mineral family chemically

described by A

2

+

3

B

3

+

2

(SiO

4

)

3

, where A

2

+

is a bivalent ion of iron, magnesium, manganese orcalcium, and B

3

+

is a trivalent ion of iron, aluminium, chromium or vanadium. According tothe combination of these bivalent and trivalent ions, different families of garnets can bedefined (Calligaro

et al

. 2002), such as almandine (Fe

2

+

,Al

3

+

) and pyrope (Mg

2

+

,Al

3

+

).In this work, garnets were analysed by PIXE using the two Si(Li) detectors set-up. The first

detector without an absorber and in a helium flow measures the X-rays emitted by elementsranging from magnesium to iron, whereas the second Si(Li) detector, with a 100

µ

m Al absorber,is dedicated to the detection of heavier elements: copper, zinc, yttrium and zirconium.

Figure 6 The (a) X-ray and (b) γ-ray spectra of a reference emerald give information on major, minor and trace elements, with detection limits at the ppm level.

https://www.researchgate.net/publication/223219395_Combined_external-beam_PIXE_and_-Raman_characterisation_of_garnets_in_Merovingian_jewellery?el=1_x_8&enrichId=rgreq-3268c19b-0156-4f7f-a607-ff45a6ba3032&enrichSource=Y292ZXJQYWdlOzIyOTYyNzMwODtBUzoxMDE5OTM2MTU5ODY2OTdAMTQwMTMyODU4MTkxMQ==

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THE VISIGOTHIC GOLD

Several analyses have been carried out on gold objects found in the Iberian Peninsula. We cancite, for instance, the hoard of Arrabalde (Perea and Rovira 1995) and the hoard of Villena(Soler Garcia 1969). However, while the composition of the gold circulating in the VisigothicIberian Peninsula is not entirely unknown, most of the published analytical data concerndebasement of gold coins.

From their invasion of the Iberian Peninsula in

ad

416 to their defeat by the Moors in

ad

711, the Visigoths struck gold coins (see, e.g., Barral i Altet 1976; Metcalf 1988). A numberof authors have considered the problem of the

tremisse debasement throughout the Visigothicdomination of Iberia (Metcalf and Schweitzer 1970; Gomes Marques et al. 1995), but only theanalytical data published by Guerra (2000) and by Guerra and Roux (2002) considers thecharacteristic trace elements of monetary gold issued from the reign of Leodegild (ad 568–86)to the reign of Witiza (ad 701–9). Data was obtained by 12 MeV proton activation analysisand the results revealed the exploitation of at least two different local gold sources.

In Book 33 of his Natural history, Pliny the Elder cites the exploitation under the Romansof two main Iberian gold districts. He refers to the exploitation of gold dust in the river Tagusvalley in Lusitania (the present Extremadura and south of the River Douro in Portugal) and tothe production of gold in Galecia (the present Asturias and Galicia). Galecia and Lusitaniaprovided about 6.5 tons of gold each year. Lehrberger (1995) and Shepherd (1993) describethe Portuguese and Spanish gold deposits. Shepherd (1993) refers to the huge gold productionof the Sil river valley, in the mining region of Las Medulas. In Figure 7, we show the differentVisigothic provinces of Iberia (Rucquois 1993) and the Visigothic mints (Gomes 1996). Some

Figure 7 The Visigothic provinces and mints of the Iberian Peninsula, as well as the main rivers where alluvial gold exploitation is mentioned by Pliny the Elder (after Rucquois 1993; Gomes 1996).

https://www.researchgate.net/publication/229601176_Milliprobe_analyses_of_some_Visigothic_Suevic_and_other_gold_coins_of_the_Early_Middle_Ages?el=1_x_8&enrichId=rgreq-3268c19b-0156-4f7f-a607-ff45a6ba3032&enrichSource=Y292ZXJQYWdlOzIyOTYyNzMwODtBUzoxMDE5OTM2MTU5ODY2OTdAMTQwMTMyODU4MTkxMQ==

The treasure of Guarrazar 61

© University of Oxford, 2007, Archaeometry 49, 1 (2007) 53–74

of these mints had a regular output of gold coins, while others were just temporary mints(Crusafont i Sabater 1994).

It can be assumed that both the northwestern and the southern Iberian mints had localsupplies. The analytical data published by Guerra (2000) and Guerra and Roux (2002) showedthat, under the Visigoths, those two gold districts could be entirely characterized by elementssuch as platinum, palladium, tin and zinc. Contrary to the northwestern district, the southerndistrict is characterized by high contents of platinum and palladium and low contents of tinand zinc. Figure 8 shows the two chemical groups formed by the ratios of platinum and tinconcentrations to gold contents for the tremissi struck in the different Visigothic mints. Table 1presents the composition of these Visigothic coins.

The comparison of Visigothic with Suevian gold coins (the composition is also presented inTable 1) confirms the characterization of the northwestern gold sources. In ad 407, togetherwith the Vandals and the Alans, the Suevians reached the Iberian Peninsula. Three years later,they settled in the northwestern part of Iberia and in ad 429 they defeated the Vandals; theysubsequently expanded up to Merida in ad 450. After the loss of this new territory to theVisigoths they moved back to Galicia, where they settled until ad 585, when Braga and Portowere conquered by the Visigothic King Leodegild.

The Suevians struck gold coins, which were copies of solidi and tremissi issued in thenames of different Roman emperors (Valentinian, Valerian, Honorius and so on). Nowadays,only 200 tremissi and 20 solidi can be attributed to the Suevians (Gomes 1996) and somedifficulties of attribution still exist for the Suevian and the pre-national Visigothic coins. Wemust keep in mind that the same types of copies were produced by the Visigoths until at leastthe reign of Leodegild. Gomes Marques et al. (1995) have identified some copies struck in thename of Justin II (ad 565–78).

When we add to Figure 8 the ratios of platinum and tin concentrations to gold contents for theSuevian coins, we can observe that some match the same chemical group as the northwesternVisigothic coins. M. Metcalf provided an explanation for the others (see Guerra 2000; Guerraand Roux 2002). This scholar assumes that the northern Visigothic coins with a southern goldpattern correspond to the remelting of southern coins. He estimates the contribution of the

Figure 8 The ratios of platinum and tin concentrations in ppm to gold contents in per cent for the gold coins struck by the Visigoths in the different Iberian mints (by province) and by the Suevians (after data from Guerra 2000; Guerra and Roux 2002).

62 M. F. Guerra, T. Calligaro and A. Perea


Table 1 The composition of the Visigothic and Suevian coins, in percent for major elements and in ppm for traceelements; measurements were carried out by 12 MeV proton activation analysis. CC, Carlos Costa’s collection

(Associação Numismática de Portugal); BNF, Bibliothèque national de Paris collection

Reign Reference MintAu (%)

Ag (%)

Cu (%)

Ru (ppm)

Pd (ppm)

Sn (ppm)

Sb (ppm)

Fe (ppm)

Pt (ppm)

Suevian CC-1 88.8 10.8 0.3 11 15 633 23 405 219CC-2 84.6 13.5 1.3 17 35 4 604 15 1 024 9CC-3 97.0 2.6 0.3 – 18 35 3 237 349CC-4 93.2 5.7 1.0 – 7 382 16 577 90CC-5 78.1 20.5 0.9 – 46 3 045 24 871 49BNF-R1889 75.5 22.7 1.5 13 158 1 573 31 601 54BNF-1992.1077 82.5 16.8 0.6 8 100 807 29 483 –BNF-L3410 80.0 18.7 0.8 30 2 3 758 26 1 081 –BNF-1966.3 89.2 10.3 0.3 3 121 1 467 32 141 –BNF-1992.1075 88.7 10.5 0.6 7 34 383 8 333 139

Leodegild CC-L1 Evora 67.6 30.0 2.1 – 12 722 16 1 122 169

Recared I CC-R1 Porto 59.2 37.3 3.1 2 103 181 1 384 32 409 58CC-R2 Braga 73.8 24.0 1.9 26 148 1 241 26 987 66CC-R3 Coimbra 74.7 23.3 1.6 – 7 3 343 7 472 33CC-R4 Evora 77.0 20.9 1.9 – 12 878 10 1 022 124CC-R5 Monsanto 75.6 22.8 1.3 – 87 1 505 21 484 81BNF-16 Mérida 82.3 16.3 0.9 12 68 2 835 13 26 33BNF-17 Evora 75.6 22.0 2.2 22 43 480 – 14 136BNF-20 Toledo 75.2 22.8 1.7 33 95 824 19 23 113BNF-21 Ispalis 76.4 21.7 1.6 18 – 706 19 877 100BNF-24 Cordoba 75.8 22.4 1.5 21 – 788 26 775 156BNF-29 Barcelona 74.4 23.7 1.5 32 – 899 16 938 139BNF-31bis Pincia 69.8 27.7 2.4 7 – – – 133 100BNF-19 Toledo 76.8 21.3 1.6 20 – 1 071 25 946 122BNF-27 Eliberri 73.1 25.3 1.5 16 – 356 – 706 146

Liuga II CC-Li1 Evora 75.4 22.5 1.9 – 33 651 9 712 110

Witterich CC-W1 Evora 76.5 22.6 0.9 3 13 73 22 89 0

Gundemar CC-G1 Idanha 73.6 25.3 0.7 – 6 3 583 38 229 –CC-G2 Evora 73.0 24.9 2.0 – 17 471 6 394 165

Sisebur CC-S1 Idanha 82.8 15.9 1.2 – 10 300 – 100 200CC-S2 Braga 68.9 29.6 0.8 – 10 4 700 20 400 20CC-S3 Evora 76.2 22.1 1.6 – 10 600 10 500 100CC-S4 Viseu 79.1 12.9 7.7 – 110 1 100 10 500 800CC-S5 Coimbra 74.8 24.6 0.2 14 333 2 770 23 773 –CC-S6 Idanha 60.2 37.8 1.8 – 12 738 12 493 100CC-S7 Monecipio 91.3 7.8 0.3 – 8 4 987 38 348 15CC-S8 Nandolas 72.4 24.9 2.6 – 32 419 – 808 95

Swinthila CC-Sv1 Evora 96.0 2.3 1.6 – 10 400 4 700 100CC-Sv2 Coimbra 64.2 33.7 1.8 30 8 1 270 16 808 117CC-Sv3 Evora 58.8 38.9 2.1 – 22 648 11 382 145CC-Sv4 Porto 69.2 28.2 2.3 – 9 614 9 759 129CC-Sv5 Braga 67.7 29.0 1.9 11 1 402 11 754 65 492 –CC-Sv6 Cepis 73.4 25.0 1.4 3 3 124 10 910 39CC-Sv7 Turiviana 82.3 14.6 2.6 – 67 1 893 12 669 –CC-Sv8 Mérida 64.1 33.5 2.0 – 8 664 19 682 128



Erwig CC-E1 Idanha 76.9 20.1 2.5 – 7 2 694 27 397 –CC-E2 Evora 74.1 23.7 1.9 – 9 546 8 980 104

Egica CC-Eg1 Idanha 64.6 15.1 20.2 5 40 0.5 29 40 170BNF-72 Taraconna 50.9 44.8 3.9 – 6 514 32 673 90BNF-78 Toledo 63.1 34.3 2.5 – 8 274 8 247 175

Egica and Witiza

CC-EW1 Evora 37.5 58.0 4.2 18 63 327 18 429 107CC-EW2 Idanha 47.7 49.7 2.1 16 231 1 910 16 619 –BNF-73 Toledo 36.0 58.4 5.1 – 5 573 18 724 55BNF-74 Cesaraugusta 40.9 54.5 4.2 – 5 609 19 772 61BNF-75 Narbona 43.7 52.9 3.1 – 6 385 10 609 79BNF-77 Gerunda 39.8 56.5 2.5 – 5 5 0 213 133

Reign Reference MintAu (%)

Ag (%)

Cu (%)

Ru (ppm)

Pd (ppm)

Sn (ppm)

Sb (ppm)

Fe (ppm)

Pt (ppm)

Table 1 (continued)

northwestern mints to the total monetary metallic mass at only about 10%. This could alreadybe the situation under the Suevians. The northwestern gold mines are assumed to have closedalready under the Romans. Our hypotheses are that (a) under the Suevians and the Visigothsthe northwestern gold district was still exploited for mint production and (b) the northwesterngold is characterized by high contents of tin and low contents of platinum and palladium.

The presence of platinum and tin in the Suevian and Visigothic monetary gold is the basisof our assumptions. On the one hand, it suggests the exploitation of secondary gold deposits—such as the gold nuggets of the River Tagus, cited by Pliny the Elder in Book 33 of his Naturalhistory—while, on the other hand, it is the Suevian and the northwestern Visigothic coins thatpresent the highest contents of tin. In Book 34, Pliny mentions the exploitation under theRomans of cassiterite in the alluvial deposits of Galicia. This last statement corroborates theassumption that high contents of tin may be characteristic of northwestern alluvial gold.

THE GOLD OF GUARRAZAR

Perea (2001) considered the composition in major elements (gold, silver and copper) of allthe crosses, crowns, chains and pendants. These analytical data, obtained by PIXE both at theC2RMF (Paris, France) for the items kept in France and at the LARN (Namur, Belgium) forthe items kept in Spain, have been published by Montero et al. (2001). The aim of this workis to accomplish the characterization of the Visigothic gold by measuring the major and the traceelement contents of 46 micro-samples from the objects kept in Spain. These measurementswere carried out by using the micro-beam PIXE–PIGE set-up at the C2RMF. The compositionof the 46 samples is presented in Table 2.

Figure 9 illustrates the quality of the Guarrazar jewellery compared with the quality of theVisigothic coins. As expected, the jewellery, with a gold content generally between 85% and95%, is of better quality than the coins. We must mention the good quality of prestige itemssuch as the crown of King Recceswinth (reference 71.202 in Table 2; for further results, seePerea 2001). If we exclude the highly debased tremissi struck under the last Visigothic kings (whowere suffering from the Arab invasion), the coins show an average fineness of around 75%.



Table 2 The composition of the samples from the treasure of Guarrazar, in percent for major elements and in ppmfor trace elements; measurements were carried out by filtered PIXE with a 3 MeV proton beam. *, Solder contamination;

**, modern repair?

Object ReferenceAu (%)

Ag (%)

Cu (%)

Ru (ppm)

Pd (ppm)

Sn (ppm)

Sb (ppm)

Fe (ppm)

Processional cross 52.561Arm A G 1 87.6 11.7 0.7 14 105 597 11 328

G 2 85.8 13.6 0.4 57 70 199 22 300G 3 87.8 11.4 0.5 13 66 263 <10 492

Arm B G 4 87.7 10.5 1.0 25 83 133 12 981G 5 87.5 12.0 0.3 19.2 28 826 25 1 364G 6 87.6 11.9 0.3 58.8 80 928 <10 1 269

Reccaswinth crown 71.202Letter V G 7 85.4 11.9 2.3 49.3 <20 198 24 3 823Letter S G 8 97.6 1.6 0.4 20 <20 47 <10 4 618Letter E G 9 87.8 4.5 7.5 <10 <20 164 47 21 895

Letter R G 10 91.5 5.8 2.3 13 66 263 <10 3 062G 11 91.7 6.2 1.9 18 27 452 <10 1 934G 12 93.4 4.1 2.3 <10 23 78 61 213G 13 93.0 4.4 2.4 24.1 54 113 26 1 187G 14 92.4 6.0 1.4 13 22 417 <10 1 568G 15 92.5 6.1 1.2 13 54 296 39 7 580G 16 67.8 30.0 1.5 74.6 94 526 43 3 125G 17 90.1 8.5 1.2 <10 52 279 25 4 642G 18 89.7 8.2 1.8 22.3 <20 168 20 1 710

Reccaswinth cross 71.203G 19 94.7 4.2 0.9 11 70 116 <10 1 324G 20 88.3 8.3 3.1 <10 55 330 26 2 155

Cross 71.205G 21 65.7 32.9 1.3 23 230 109 17 67G 22 85.0 12.8 1.4 <10 111 302 <10 77

Crown 71.204G 23 82.1 13.2 4.8 <10 155 145 <10 1 025G 24 65.5 30.9 3.3 <10 143 305 231 925G 25 88.8 8.6 1.6 24 100 71 20 9 289G 26* 64.5 32.1 3.3 49

Crown 71.207G 27 83.3 15.2 1.5 29 105 453 <10 477G 28 82.5 13.0 4.2 56.2 <20 662 <10 1 142G 29 86.2 10.7 2.8 <10 52 318 17 1 179G 30 95.4 3.1 1.0 27 42 177 <10 1 552

Crown 71.206G 31 87.5 11.7 0.8 <10 85 353 13 381G 32 88.1 10.5 1.2 12 125 456 32 674G 33 92.3 5.3 2.1 16.8 83 70 20 4 052G 34 87.4 9.9 1.5 32.9 67 242 <10 8 648

Crown 71.208G 35** 75.6 22.4 1.6 15 94 421 <10 451G 36 85.4 13.1 1.5 28 43 415 <10 1 858G 37 92.4 4.9 2.7 36 25 250 11 1 461G 38 93.8 4.4 1.2 34 <20 114 <10 2 898G 39 93.2 3.6 2.3 20.5 53 56 <10 7 426



Cross 71.210G 40** 75.2 21.3 3.2 <10 62 591 <10 680G 41** 76.8 20.3 2.9 11 98 598 <10 637G 42 86.3 10.5 2.7 56.3 84 1 099 38 1 421G 43 92.6 4.7 2.2 28 39 256 29 2 665

Cross 71.211G 44** 77.6 20.1 2.1 107 70 414 14 358G 45** 77.4 20.7 1.8 11 80 713 11 709G 46 88.3 9.1 2.5 20 44 179 <10 252

Object ReferenceAu (%)

Ag (%)

Cu (%)

Ru (ppm)

Pd (ppm)

Sn (ppm)

Sb (ppm)

Fe (ppm)

If we exclude one Guarrazar sample and one coin, the copper contents for both the coinsand the jewels are below 5%. The silver contents of the coins issued by the last Visigothickings may, however, attain as much as 60%, most probably due to the addition of silver or theuse of a non-refined—possibly natural—silver–gold alloy (Guerra 2000).

Unfortunately, zinc, which proved to be relevant for the characterization of the IberianVisigothic gold, is present in the Visigothic jewellery at concentrations lower than the detectionlimits of filtered PIXE. In addition to this, as mentioned above, platinum could not be measuredby PIXE–XRF for such small samples (Guerra et al. 2004).

For ruthenium and antimony, if we exclude two samples, we were able to show the following.The ruthenium contents, which range from 10 to 60 ppm, can be said to match the range of1 to 30 ppm measured for all but one of the coins struck under King Recaredus. The antimonycontents are in the same range of concentration as ruthenium for both the jewellery and the coins.

Figure 10 illustrates the concentrations of palladium and tin for both the Visigothic coinsand the Guarrazar jewellery. Due to their very high ratios of tin to gold, the northwestern coins

Figure 9 The gold contents of the Visigothic coins and the Guarrazar samples.

Table 2 (continued)




have not been considered in this figure. All but four of the samples form a quite homogeneouschemical region characterized by low contents of tin and palladium, which tends to confirmthe use of a local gold to fabricate the jewellery. If we consider the gold mining regionsmentioned by Pliny, this gold could come from the region of the River Tagus, in Lusitania andCarthaginensis. The goldsmiths could also have used some northwestern gold, but in quantitiesthat are too low to be detected. We must remember that the northwestern mines, being unableto produce enough gold to supply the royal mints, could hardly be exploited to fabricate thejewellery.

The four samples with higher contents of palladium (Fig. 10) correspond to two crowns thatare typologically similar (references 71.204 and 71.205 of Table 2). These crowns consist of acirclet of thick gold chased and in repoussé (only 71.204 is set with sapphires and nacre) andcould be either imported or fabricated with imported gold, Roman or Byzantine. Unfortunately,the analytical data published by Morrisson et al. (1985) for Byzantine coins struck from JustinII to Irene (ad 565–802) do not consider both tin and palladium. Only platinum, ranging from250 to 400 ppm, is cited as characteristic of this origin. However, the average ratio of platinumin ppm to gold content in percent for the Byzantine coins is 3.7 ± 0.8, while for Iberianmonetary gold this ratio only attains 1.3 ± 0.9.

Very few data are available on trace element concentrations of Roman gold coins. However,Poirier (1983) was able to demonstrate a change in the gold supplies of the royal mints afterValentinian’s reform of ad 368. Figure 11 shows the ratios of palladium and tin to gold contentsfor six Roman coins issued between ad 368 and ad 375, published by Poirier (1983), togetherwith the south Iberian Visigothic coins and the Guarrazar jewellery. Roman gold cannotexplain the trace element pattern of the two crowns of Guarrazar, which does not match theIberian gold.

Apart from the suspicion of the use of imported Byzantine gold (or of its remelting and reuse),no explanation could be found for such a difference. In order to evaluate the concentration ofplatinum in those particular samples, an experimental set-up for the measurement of this elementis being developed by using synchrotron radiation XRF at BESSY II (Berlin), in collaborationwith the BAM team.

Figure 10 The ratios of the palladium and tin concentrations in ppm to the gold content in per cent for the Guarrazarsamples displayed by object.



THE GEMSTONES OF GUARRAZAR

Like other pieces of jewellery from the Dark Ages, the crosses and crowns of Guarrazar areadorned with many gemstones and coloured glass beads. The gemstones occur as cabochonsset in rounded bezels, pierced beads hanging on pendants or thin slabs inlaid in the cloisonnéparts of the crowns. The different types of gems, generally arranged in a symmetric pattern,are white quartz, sapphires, pearls and mother-of-pearl, red garnets and chalcedony, pinkamethysts, blue sapphires and cordierites, green emeralds and lead-glass beads.

The gemstones of the pieces kept in Madrid have been studied previously (Cozar andSapalski 1996). In this section, we summarize the results obtained on the jewellery kept in theFrench collection (some data has already been published in Calligaro et al. 2000a, 2001a,c,d).

The bulk chemical compositions determined by PIXE–PIGE allowed us to directly identifythe gemstones (Calligaro et al. 2001a) and to specify the type of glass beads inlaid in thejewellery. Trace elements, fingerprinting emeralds (Calligaro et al. 2000a, 2001c,d) and garnets,were used to propose a provenance. The study of the gemstones complements the resultsobtained for the gold, which suggest the exploitation of local Iberian sources, and shows amore diversified supply for the gemstones.

Gemmological observations of the sapphires yielded some information concerning theirprovenance. Their colour, which ranges from almost transparent to light blue, their large size(up to 19 mm × 18 mm) and the presence of very long needle-like rutile inclusions (TiO2)typically correspond to sapphires occurring in Sri Lanka. This is in good agreement with theancient writings of the first century ad by Pliny the Elder (1983) and of the sixth century adby Cosmas Indicopleustes (see Wolska-Conus 1973). Both authors cite Taprobane in Sri Lankaas a source for sapphires (and also amethysts). We have also noted that, contrary to othergemstones set in bezels, many sapphires are drilled and some are engraved, suggesting apossible reuse of the blue stones from Roman necklaces.

The provenance of the pearls and the inlays of mother-of-pearl could not be precisely specified,but can only be oriental (the Red Sea, the Persian Gulf, the Gulf of Mannar and the coasts ofIndia). Conversely, little could be said about the quartz and the amethysts. These widespread gemsexhibit few trace elements and occur in many European locations, including the Iberian Peninsula.

Figure 11 The ratios of the palladium and tin concentrations in ppm to the gold content in per cent for the Guarrazarsamples, the south Iberian coins and Roman coins.



Garnets

Two garnets remained in the cloisonné of the pendant, representing an ‘R’ from the Recceswinthcrown fringe of pendants, with gold letters spelling ‘+RECCESVINTHUS REX OFFERET’.Cozar and Sapalski (2001) have reported a large number of garnets of intermediate pyrope–almandine composition in the Spanish pieces. In the case of the ‘R’ pendant, Table 3 showsthat the two garnets studied have a dominant pyrope component (Mg-rich) combined withrather high titanium (0.4% TiO2) and low chromium (0.01%) concentrations.

The comparison of published data on medieval garnets with our results is rather interesting.Indeed, as garnets are the most common gemstones employed in jewellery from the DarkAges, the question of their origin has been investigated for 50 years (Farges 1998; Greiff1998; Quast and Schüssler 2000). It is generally assumed that they were imported from India,with a sudden change of supply occurring at the end of the sixth century ad, due to the closingof the commercial routes towards the east. To test and refine this hypothesis, we have undertakena research programme on more than 1000 garnets included in Merovingian jewels (Calligaroet al. 2002), as well as on reference garnets from various sources. On the basis of the chemicalcomposition obtained by PIXE and the identification of mineral inclusions by Ramanspectrometry, we have been able to place the Merovingian garnets into five distinct groups,labelled type I to type V, and to assign a geographical origin to four of these groups. Mostmedieval garnets (80%) are almandines (Fe-rich) and are categorized as type I or type II.These types have different chromium and yttrium contents and correspond to two differentgarnet sources in India. The type III gemstones are intermediate pyrope–almandine garnetsthat typically occur in Sri Lanka. The two last types (IV and V) are pyropes (Mg-rich). TypeIV does not contain any chromium, while type V contains ∼2.2% Cr2O3. Type V definitely corre-sponds to deposits in the Bohemian massif (Czech Republic). The fact that garnets of types IVand V were the only ones employed for objects dating from the sixth century ad onwardscorroborates the above-mentioned hypothesis of a change of supply. As can be seen in Figure 12,the garnets of the pendant of the crown of King Recceswinth belong to the peculiar type IV,interestingly also observed on a few objects unearthed from the necropolis of Saint-Denis, suchas the belt-buckle and the long needle of the Merovingian Queen Aregonde (∼ ad 500–80).

Table 3 The composition of the two garnets of Guarrazar compared with the five groups observed in the literature(Calligaro et al. 2002) and with reference garnets from Hoyazazo, Almeria, Spain. The two gemstones belong to type IV,

which are pyropes, probably of European origin

MgO Al2O3 SiO2 CaO TiO2 Cr2O3 MnO FeO Y2O3

GuarrazarGarnet 1 17.4 25.1 41.2 5.3 0.3 0.01 0.3 10.1 0.00Garnet 2 15.5 23.1 41.5 5.8 0.4 0.01 0.4 13.1 0.00

GroupsType I 4.4 20.8 36.0 0.7 0.01 0.01 0.4 37.5 0.01Type II 6.2 21.5 37.3 1.4 0.03 0.06 1.2 32.1 0.06Type III 11.7 22.5 39.3 2.6 0.05 0.02 0.6 23.0 0.02Type IV 16.3 23.1 41.2 5.4 0.4 0.02 0.4 12.7 0.01Type V 19.8 21.6 41.5 4.3 0.4 2.2 0.3 8.9 0.00Almeria 3.5 21.0 37.0 1.2 0.05 0.01 1.0 36.0 0.04



Although we have not yet located the source of these type IV garnets, the fact that they oftenappear in combination with type V garnets from Bohemia is a pointer towards a Europeanorigin. We should also mention a source of garnets in Almeria, in the south of Spain, but thedata in Table 3 show that they have a totally different composition (almost pure almandine).

Emeralds

The 11 emeralds set on two crowns kept in Paris have colours ranging from light to deepgreen, according to their chromium contents, and are shaped in cabochons. To determine theorigin of these emeralds, we have carried out about 170 measurements on reference emeraldsfrom various sources: Austria (Habachtal), Colombia, Afghanistan (Panshir), Russia (theUrals), Madagascar (Manajany), India (Adjemer), Egypt (D. Zabara), Zimbabwe (Sandawana),Pakistan (Swat), Norway (Eidswoll), Brazil (a variety of sources) and Zambia (Calligaro et al.2001d). Some of these sources are not relevant for the comparison with medieval gemstones,but the data obtained was useful for the purpose of selecting the most discriminating chemicalelements for provenancing. Despite its heterogeneous distribution, lithium turns out to be agood provenance indicator. Emeralds from Russia, Zimbabwe and Zambia are characterizedby high contents of this element (> 500 ppm). Emerald deposits from Colombia, Afghanistanand Norway are characterized by high concentrations of vanadium (> 500 ppm) and thesources located in Zimbabwe, Zambia and Madagascar show a marked concentration ofrubidium (> 100 ppm).

Figure 12 A comparison of the MgO, FeO and CaO contents measured for the garnets of Guarrazar with data fromMerovingian jewellery.



The emeralds set on the crowns of Guarrazar showed low vanadium (< 500 ppm), rubidium(< 40 ppm) and lithium (< 200 ppm) concentrations. These results eliminate several sources:Colombia, Zimbabwe, Zambia, Madagascar, Russia and India. In addition to this, the highsodium (2.3% Na2O) and zinc (> 30 ppm) concentrations observed in the ancient emeraldsdo not match the chemical fingerprint of Afghan and Pakistani deposits. This leaves Austriaand Egypt as the only possible sources for the Visigothic emeralds. To decide between thesetwo possible provenances, the full set of trace elements was processed using multivariatestatistical methods (Calligaro et al. 2001a,c). The results of this statistical analysis, presentedin Table 4, show with a confidence level ranging from 60% to 99% that all but one of theemeralds considered were extracted from the Habachtal mines, near Salzburg in the AustrianAlps.

Three sources of emeralds exploited under the Romans are explicitly cited by Pliny theElder in Book 37 of the Natural history—Egypt, Bactria (Pakistan, Afghanistan) and Scythia(probably the Urals)—but no reference can be found to a European source. The Habachtalmines are referred to for the first time in a letter from the 13th century ad, by the Archbishopof Salzburg (Calligaro et al. 2001d). These results obtained therefore suggest that theVisigothic and the Roman commercial circuits for emeralds were different.

CONCLUSIONS

The analyses of ancient jewellery have given information on goldsmithing techniques and alsoon the raw materials supplies. In general, these studies must be carried out by non-invasivetechniques that offer point analysis. Even when sampling is permitted, we might be restrainedby the preservation of the sample. We have shown in this work that the combination oftwo ion-beam techniques, PIXE and PIGE, with an external micro-beam and suitable X-rayabsorbers, is a good compromise to determine the major and some trace elements of gold aswell as of gemstones.

Different objects belonging to the treasure found in Guarrazar in the 19th century have beensampled and analysed for the provenance of gold. To characterize the metal circulating in theIberian Peninsula in the sixth and seventh centuries ad and to identify whether local or externalsources were exploited, Visigothic gold coins produced by local mints have been used asreference material. It was expected that these coins had been struck using local gold.

The results obtained for both the jewellery and the coins have been compared. Publisheddata on Roman and Byzantine monetary gold have also been considered to check for theprovenance of Visigothic gold. The presence of tin, palladium and platinum allows us to suggestthe exploitation of secondary gold deposits. However, according to their geographical origin,the coins were produced using different gold supplies. The identification of these suppliesallows us to suggest an origin for the Guarrazar gold: the southern deposits of Iberia. Theinformation given by Pliny the Elder in his Natural history on Iberian gold sources suggeststhe exploitation of the gold district around the River Tagus. However, we can imagine theexploitation of a larger mining district.

To complement this work dedicated to the provenance of gold, we have considered the natureand the provenance of the gemstones inlaid in a few crowns and crosses from Guarrazar. Theanalytical data provides an overview of the raw materials employed: while the pearls andsapphires have an oriental origin, the garnets probably originated from European deposits, asdid the emeralds, which were provided by the Habachtal mines in the Austrian Alps, a sourcenot reported by the Romans.

The treasure of G

uarrazar71

© U

niversity of Oxford, 2007, A

rchaeometry 49, 1 (2007) 53

–74

Table 4 The upper part of the table gives the mean composition of the emeralds of Guarrazar compared with 170 reference emeralds from various deposits. LOD denotes ‘limit of detection’and the standard deviations are given in parentheses. The lower part of the table shows the results of the statistical analysis (discriminant analysis) performed on all chemical compositions.

Ten of 11 archaeological emeralds are assigned an Alpine origin (Habachtal mines, Austria)

Calculated provenance probabilities for the 11 emeralds of Guarrazar (result of discriminant analysis)

Guarrazar (11 samples)

Austria (13 samples)

Egypt (6 samples)

Russia (20 samples)

Afghanistan (5 samples)

Pakistan (4 samples)

India (8 samples)

Norway (2 samples)

Colombia (17 samples)

Madagascar (12 samples)

Zambia (11 samples)

Zimbabwe (22 samples)

Brazil (8 samples)

LOD

Main constituents (wt%)BeO 12.0 (0.0) 11.0 (0.6) 12.1 (0.6) 11.6 (1.0) 13.2 (1.6) 12.2 (0.4) 12.3 (0.4) 13.0 (0.7) 13.0 (1.5) 13.2 (0.7) 14.2 (1.3) 13.2 (1.0) 12.5 (0.6) 0.20Na2O 2.3 (0.07) 2.1 (0.3) 2.6 (0.3) 1.7 (0.4) 1.5 (0.4) 2.4 (0.4) 1.8 (0.2) 0.3 (0.1) 0.7 (0.3) 2.2 (1.1) 1.9 (0.3) 2.8 (0.4) 2.4 (1.0) 0.03MgO 2.8 (0.2) 2.7 (0.3) 2.9 (0.5) 2.1 (1.3) 1.8 (0.5) 2.9 (0.1) 1.8 (0.4) 0.15 (0.0) 1.0 (0.4) 2.6 (0.6) 2.3 (0.7) 3.3 (0.7) 2.5 (0.8) 0.02Al2O3 15.4 (0.4) 15.4 (0.4) 15.4 (1.0) 17.1 (1.1) 16.6 (0.3) 14.4 (0.3) 16.8 (0.9) 18.3 (0.1) 18.3 (0.7) 14.5 (0.8) 14.7 (1.5) 14.0 (0.9) 15.3 (1.3) 0.02SiO2 66.4 (0.3) 67.7 (0.7) 65.6 (0.4) 66.7 (2.2) 65.9 (0.9) 66.0 (0.9) 66.5 (0.3) 66.5 (0.7) 66.6 (1.4) 65.0 (1.4) 64.9 (1.1) 64.8 (1.1) 65.6 (1.2) 0.01K2O 0.06 (0.02) 0.04 (0.03) 0.06 (0.02) 0.15 (0.48) 0.05 (0.02) 0.03 (0.02) 0.04 (0.02) 0.04 (0.01) 0.01 (0.01) 0.24 (0.12) 0.06 (0.02) 0.05 (0.05) 0.06 (0.09) 0.01CaO 0.07 (0.02) 0.06 (0.05) 0.03 (0.02) 0.03 (0.03) 0.00 (0.01) 0.03 (0.02) 0.03 (0.02) 0.04 (0.02) 0.00 (0.01) 0.08 (0.04) 0.05 (0.04) 0.03 (0.04) 0.02 (0.03) 0.00

Trace elements (µg g−1)Li 70 (10) 190 (210) 110 (20) 720 (260) 160 (69) 350 (130) 560 (340) 25 (21) 190 (170) 130 (70) 580 (230) 800 (310) 170 (90) 50F 480 (30) 225 (260) 30 (10) 220 (620) 100 (160) 35 (10) 18 (19) 60 (0) 260 (160) 75 (100) 17 (14) 34 (21) 25 (15) 60Ti 20 (24) 30 (70) 7 (7) 15 (6) 12 (9) 10 (11) 0 (0) 6 (8) 6 (8) 1 (3) 12 (40) 120 (250) 1 (4) 30V 230 (180) 170 (100) 330 (60) 130 (80) 970 (790) 320 (250) 200 (140) 6 680 (950) 1 250 (620) 130 (50) 180 (100) 210 (320) 200 (100) 10Cr 1 600 (2 300) 1 390 (720) 2 600 (1 820) 830 (630) 2 650 (330) 5 930 (1 930) 720 (420) 1 930 (20) 890 (1 070) 2 650 (1 290) 2 570 (1 500) 5 211 (2 190) 3 960 (2 540) 10Mn 15 (8) 26 (22) 22 (10) 27 (30) 17 (8) 38 (20) 20 (13) 36 (20) 5 (7) 20 (30) 30 (30) 180 (360) 24 (26) 20Fe 3 830 (760) 4 000 (1 950) 4 600 (1 710) 3 210 (1 510) 2 080 (930) 6 230 (4 250) 3 420 (1 300) 1 130 (20) 700 (560) 11 400 (2 810) 9 830 (4 880) 6 320 (3 300) 4 900 (1 250) 3Ni 23 (16) 10 (6) 5 (2) 25 (27) 1 (1) 15 (10) 15 (5) 2 (0) 0 (1) 50 (40) 15 (4) 20 (11) 13 (10) 2Cu 14 (9) 4 (5) 3 (3) 5 (7) 1 (1) 3 (2) 1 (1) 3 (2) 0 (0) 2 (3) 1 (1) 1 (2) 1 (1) 2Zn 36 (7) 14 (6) 18 (10) 40 (30) 1 (1) 4 (1) 50 (36) 30 (2) 0 (0) 30 (30) 45 (26) 66 (28) 7 (5) 2Ga 10 (1) 11 (4) 9 (1) 14 (6) 16 (3) 5 (2) 15 (8) 34 (13) 30 (10) 8 (3) 13 (5) 30 (9) 19 (6) 2Rb 17 (5) 18 (13) 24 (12) 40 (60) 30 (20) 6 (3) 30 (20) 60 (40) 2 (1) 190 (70) 140 (60) 350 (200) 15 (2) 2Cs 130 (110) 370 (390) 160 (90) 360 (230) 60 (70) 120 (80) 670 (470) 110 (70) 60 (90) 610 (580) 1 150 (540) 710 (320) 350 (300) 100

Austria Egypt Russia Afghanistan Pakistan India Norway Colombia Madagascar Zambia Zimbabwe Brazil

Emerald 1 0.840 0.004 0.150 0.001 0.002 0.000 0.000 0.001 0.000 0.000 0.000 0.002Emerald 2 0.988 0.001 0.010 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000Emerald 3 0.596 0.316 0.005 0.001 0.001 0.015 0.000 0.000 0.000 0.000 0.000 0.066Emerald 4 0.744 0.001 0.096 0.013 0.145 0.000 0.000 0.001 0.000 0.000 0.000 0.000Emerald 5 0.295 0.638 0.001 0.000 0.000 0.023 0.000 0.000 0.000 0.000 0.000 0.042Emerald 6 0.998 0.000 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000Emerald 7 0.642 0.158 0.030 0.007 0.005 0.040 0.000 0.001 0.000 0.000 0.000 0.118Emerald 8 0.611 0.062 0.203 0.009 0.011 0.020 0.000 0.003 0.000 0.000 0.000 0.081Emerald 9 0.964 0.000 0.035 0.000 0.000 0.000 0.000 0.001 0.000 0.000 0.000 0.000Emerald 10 0.998 0.000 0.002 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000Emerald 11 0.817 0.001 0.158 0.003 0.000 0.000 0.000 0.019 0.000 0.000 0.000 0.001



When we put together all of the analytical results obtained for the different materialsused in the fabrication of the jewellery from Guarrazar, we notice the use of Iberian gold andwestern European gemstones. These results suggest the use by the Visigoths of Europeanresources rather than the Roman commercial routes.

ACKNOWLEDGEMENTS

Concerning the coins, the authors are grateful to Carlos Costa and Francisco Magro from theAssociação Numismática de Portugal, to Michel Dhénin from the Bibliothèque nationale deFrance and to Michael Metcalf from the Ashmolean Museum of Oxford. Regarding thetreasure of Guarrazar, the authors are grateful to the Museo Arqueologico National in Madridand to the Musée national du Moyen Age in Paris.

The authors are also grateful to the EC COST action G8, especially to Guy Demortier fromthe LARN in Namur, and to the team of the AGLAE accelerator at the C2RMF, especiallyJoseph Salomon, Jean-Claude Dran and Ina Reiche.

The authors would like to thank M. Jean-Paul Poirot and M. Pierre-Jacques Chiappero fortheir expertise and the supply of reference gemstones.

REFERENCES

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THE TREASURE OF GUARRAZAR: TRACING THE GOLD SUPPLIES IN THE VISIGOTHIC IBERIAN PENINSULA*