NON-DESTRUCTIVE STUDY ON A CHALICE FROM BENEDICTINE ABBEY OF EINSIEDELN. Marie Wörle 1*

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1 NON-DESTRUCTIVE STUDY ON A CHALICE FROM BENEDICTINE ABBEY OF EINSIEDELN Marie Wörle 1* Karampelas S. 2 and Hunger K Swiss National Museum, Lindenmoostrasse 1, CH-8910 Affoltern am Albis, Switzerland, * corresponding author: Marie.Woerle@snm.admin.ch 2 Gübelin Gem Lab, Maihofstrasse 102, CH-6006 Lucerne, Switzerland Key words: EDXRF, Raman, Gems Introduction A group of four sacral objects, belonging to the Einsiedeln Abbey, Switzerland, preserved for centuries has recently come to light. These objects were loaned for one month to the Collection Centre of the Swiss National Museum for identification of the coloured stones and metals used in their creation. This corpus is constituted by three chalices made in beginning of the XVII century and one ciborium (1) made at the end of the XVI century. In this article the results of the study on the richest in terms of gems and pearls chalice, is described. The chalice is made of gold and enamel, and it is adorned with 63 coloured gems and 150 pearls. For detailed information regarding the history, the stylistic and iconographic description of the object could be found to Distelberger and Lanz (2). The goal of the study was to characterize the alloys and the gems which adorned this item. The results of this study were compared with the observations of Father Eustach Tonassini (3), who was in charge of the treasury between 1794 and The analyses took place in the laboratory for conservation research at the Collection Centre in Affoltern am Albis in collaboration with conservator and curator from the museum and also with scientists from the gemmology laboratory Gem Lab Gübelin in Lucerne Description of the chalice and methods used The chalice was made of gold by Matthäus Fend, a goldsmith from Ausgburg in Germany, in 1605, and it was decorated with enamel, coloured stones and pearls (Figure 1). It is 280 mm high, with 113 mm bowl diameter, 163 mm foot diameter and a total weight of 1450g. This object was inventoried by Father Eustach Tonassini, who was in charge of the treasury of Einsiedeln Abbey between 1794 and 1798 (Figure 2). All original documents about the order, the design and construction of the chalice as the inventory live through centuries and belong to the archive of Einsiedeln Abbey. The analyses took place in the laboratory for conservation research at the Collection Centre in Affoltern am Albis. Only non-destructive analytical methods could be used to examine this artefact. The chalice 1609 was difficult to handle and due to the conservation state of the object, dismantling of the different piece was excluded. Raman spectra on the accessible gems were obtained with a Horiba Jobin Yvon, Labram Aramis spectrometer coupled to an Olympus microscope. Due to the geometry of the object, an additional L-shaped lens was use (4-5) for the analysis with an objective x10 and a camera for the adequate positioning of the beam. Measurements were carried out using excitation wavelengths of 532 nm (Nd:YAG laser), 633 nm (He:Ne Laser) and 785 nm (diode laser). To confirm the results, measurements were made at least at two different points. All Raman spectra were compared to the Gübelin Gem Lab s reference spectra as well as those in the RRUFF project ( Semi-quantitative chemical analyses were performed by using a micro X-ray fluorescence spectrometer. The energy dispersive X-ray fluorescence spectrometer is equipped with an Edax Eagle III XXL micro analyser, a lens for micro measurements (spot size average 50 m) and has a large sample chamber (700x700x700 mm). An X-ray tube with a rhodium anode was used under the following conditions: no filter, 20kV, 100 A, a life time of 200 seconds per measurement and 30 points per measurement area. Sometimes, when gems were positioned in a cavity, the X-ray-spot could not reach the stones for the analyses. Classic gemmological 1

2 examinations were performed using a Zeiss Stemi 2000 CS binocular microscope equipped with a fiberoptic light source and a camera attached. The geometry of the object, the position of the gems and their mounting has impeded the handling under the microscope, affecting the quality of the photos. Fluorescence reactions of the stones were also studied under long wave (366 nm) and short wave (254 nm) UV radiation with an 8 Watt UV lamp from System Eickhorst UV. When possible, gems identification was made by Raman spectroscopy and -XRF was used in order to confirm the results. Metal alloys and pearls were analysed by -XRF. Results and discussion This object presents a rupture in the style between the foot and the part constituted by the stem and the cup. Ornaments and gems setting are different in both parts. Different elements of the chalice were analysed with the -XRF such as the bowl, the knop, the inner foot as well as the outer foot, marks, figures, some screws and gems settings, in order to check that this object was made in several periods or not. The compositions of the alloys are very similar for the bowl, the knop and the foot. More in details, the alloy consists of gold (86 to 87%), silver (7 to 8 %) and copper (5%). The alloys used for marks, ornaments, screws and gems setting contain more silver (8 to 10%) and copper (8%) than for the other parts. The results do not show that at different periods, different alloys were used for making the bowl, the stem and the foot. The chalice is adorned with 63 colour stones and 150 pearls. All pearls were mainly baroque shaped.. Some of them they show some alteration, probably because of pearls organic matter decomposition, frequently observed to old pearls. All pearls analysed by -XRF, show very low concentrations of manganese (around the detection limit of the instrument) and minor concentration of strontium (6). These are indicating that there are saltwater pearls. Coloured stones are held in closed back setting, they are shaped in various forms such as oval, rectangular, octagonal and square and were cabochons, step cut and rose cut (7-8). The cuts are well known since the XVI century. The coloured stones width varied from 4.3 to 15.2 mm. The classic gemmological observations did not find indications of doublets, imitations, glasses or synthetics. By using Raman spectrometer and EDXRF it is found that the identification of the stones by Father Eustache Tonassini made at the end of the 18 th century was in mainly accurate; table 1 presents for each stone both identifications. More in details, ten of the eleven orange coloured stones identified by Father Eustache Tonassini as Hyacinth, were identified as garnets from the ugrandite group, mainly grossular (the two most intense Raman bands are about 380 and 885 cm -1 ; see an example in Figure 3), and one of them as a garnet from the pyralspite group, mainly almandine (the two most intense Raman bands are around 360 and 923 cm -1 ; see an example in Figure 4). Moreover, in Father Tonassini s manuscript when a stone was identified as a Granat, the stone was red, the Raman spectroscopy analysis demonstrated that it was garnet from the pyralspite group mainly almandine. Sometimes he was uncertain and wrote Granat or Rubin, for red coloured stones. These stones also are garnets, from the pyralspite group (mainly almandine). Additionally, Father Eustache Tonassini identified twenty gems as Rubin. Three of them were characterised by Raman spectroscopy as garnets from the pyralspite group (mainly almandine) and seventeen of them were identified by Raman spectroscopy as corundum, a ruby; the main Raman band of corundum at about 422 cm -1 under excitation at 785 nm. Using the laser at 632 nm an intense doublet at about 1375 and 1405 cm -1 was observed. This doublet is not a Raman signal but rather photoluminescence due to emission lines of Cr ions in the ruby. Seven stones named as an Amethyst (i.e., purple quartz) by Father Eustache Tonassini were purple colour stones. Five of them have been identified by Raman spectroscopy as quartz (intense Raman band at about 467 cm -1 ). Two of them have been identified by Raman as garnet from the pyralspite group, mainly almandine. From the five stones described by Father Eustache Tonassini as Saphyr, four of them are light blue and one of them is light green. The four light blue stones have been identified with Raman spectroscopy as corundum, in this case sapphires (main Raman band at 419 cm -1 using the 785 nm laser and Cr ions emission bands at 1372 and 1401 cm- 1 using the laser at 632 nm). The light green stone has been identified as olivine (peridot) (two intense Raman bands at about 826 and 858 cm -1 ). The four other light green stones called Chrysolith by Father Eustache Tonassini have been identified also as olivines 2

3 (peridot). From the eight green stones called Smaragd in the inventory, six of them have been identified also as olivines and two of them as beryls; emerald (Raman bands at about 698 and 1079 cm -1 ). The light yellow-orange stone typified as Topaz, has been with Raman spectroscopy identified as quartz (yellow coloured quartz is called citrine). The transparent stone with a light grey colour was named Weislochstein. This stone shows a sharp band at 1338 cm -1, characteristical for diamonds. Finally three red stones on the knop, drawn in the inventory but not described in the manuscript, have been identified as garnets, from the pyralspite group, mainly almandine. Conclusion. The non destructive analyses of the Einsiedeln Chalice carried out in the laboratory for conservation research at the Collection Centre at the Swiss National Museum, showed that the artefact was made from gold rich alloys and decorated with 63 coloured stones and 150 pearls, all naturals. All the stones have old cuts. It was no evidence that any were doublets or imitations, contrary to studies on other historical objects (9). Using Raman and EDXRF, the coloured stones were identified, as garnets, sapphires, rubies, citrines, amethysts, peridots, emeralds and diamond. The pearls are all saltwater. Due to the geometry of the object, it was not possible to do X-radiography on the in order to inspect their internal structure and to prove their natural origin. However, their appearance, the fact that there are old and that no bead was observed inspecting their drill holes are strong indications that the pearls are natural. The Father Eustache Tonassini mentioned in his inventory the use of arabisches Gold, Orientalisch Stones and Weislochstein. Further research would be needed to know the provenance of the used materials: gold, stones and pearls. References (1) Stefanos Karampelas, Marie Wörle, Katja Hunger, Hanspeter Lanz, Danilo Bersani Susy Gübelin, A study of the gems in a ciborium from Einsiedeln Abbey, Gems and Gemology, Vol.46, N.4, p , (2) Rudolf Distelberger, Hanspeter Lanz, Gold für das seelenheil kostbare weihegeschenke an die Madonna von Einsiedeln aus der Zeit um 1600, Journal of Swiss Archeology and Art History, Vol. 66, N.4, p , (3) Father Eustache Tonassini, Beschreibung des Kirchenschatzes Teil I, Archive of Einsiedeln, Switzerland, (4) Michèle Pinet, David C. Smith, Bernard Lasnier, Utilité de la microsonde Raman pour l identification des gemmes, Revue de gemmologie, Hors série p11-60, (5) Danilo Bersani, Pier Paolo Lottici, Applications of Raman spectroscopy to gemology, Anal. Bioanal. Chem., 2010, 397: (6) Winfried Gutmannsbauer, Morphologische, Strukturelle und Chemische Untersuchungen an Perlmutter und Perlen einiger Perlenbildender Muschel,Diplomarbeit, Philosophisch Naturwissenschaftliche Fakultät der Universität Basel, 1992, (7) Benvenuto Cellini, Traité de l orfèvrerie et de la sculpture, Edition énsb-a, 1992 (8) Herbert Tillander, Diamond cuts in Historic Jewellery, , Art Books International,

4 (9) Ina Reiche, Sandrine Pages-Camagna and Lothar Lambacher, In situ Raman spectroscopy investigations of the adorning gemstones on the reliquary Heinrich s Cross from the treasury of Basel Cathedral, Journal of Raman Spectroscopy, Vol. 35, p ,

5 gem s numbering color laboratory s results Identification Tomasini CN1S1 orange garnet, ugrandite group ( mainly grossular) Hyacinth CC1S2 red ruby Rubin CN1S3 orange garnet, ugrandite group ( mainly grossular) Hyacinth CN1S4 red ruby Rubin CN1S5 purple quartz, amethyst Amethyst CN1S6 red ruby Rubin CN1S7 purple garnet, pyralspite group (mainly almandine) Amethyst CN1S8 red ruby Rubin CN1S9 blue sapphire Saphyr CN1S10 red ruby Rubin CN1S11 red garnet, pyralspite group (mainly almandine) Rubin CN1S12 red ruby Rubin CN2S1 droit red garnet, pyralspite group (mainly almandine) Cremoneser Granat CN2S1 gauche red garnet, pyralspite group (mainly almandine) Cremoneser Granat CN2S2 blue sapphire Saphyr CN2S3 red garnet, pyralspite group (mainly almandine) Granat oder Rubin CN2S4 green peridot (olivine) Chrysolith CN2S5 dark orange garnet, ugrandite group ( mainly grossular) Hyacinth CN2S6 purple garnet, pyralspite group (mainly almandine) Amethyst CN2S7 green peridot (olivine) Chrysolith CN2S8 green peridot (olivine) Chrysolith CN2S9 light yellow citrine Topaz CN2S10 orange garnet, ugrandite group ( mainly grossular) Haycinth CN2S11 purple quartz, amethyst Amethyst CN2S12 blue sapphire Saphyr CN3S1 red garnet, ugrandite group ( mainly grossular) Hyacinth CN3S2 red ruby Rubin CN3S3 green peridot (olivine) Saphyr CN3S4 red ruby Rubin CN3S5 red garnet, pyralspite group (mainly almandine) Rubin CN3S6 red ruby Rubin CN3S7 red garnet, pyralspite group (mainly almandine) Rubin CN3S8 red Rubin Rubin CN3S9 red garnet, pyralspite group (mainly almandine) Granat CN3S10 red ruby Rubin CN3S11 orange garnet, ugrandite group ( mainly grossular) Hyacinth CN3S12 red ruby Rubin KN1S1 orange garnet, ugrandite group ( mainly grossular) Hyacinth KN1S2 red ruby Rubin KN1S3 red garnet, pyralspite group (mainly almandine) Hyacinth 5

6 KN1S4 green emerald Smaragd KN1S5 green peridot (olivine) Chrysolith KN1S6 red ruby Rubin KN2S1 red garnet, pyralspite group (mainly almandine) Pas d identification* KN2S2 blue sapphire Saphyr KN2S3 red garnet, pyralspite group (mainly almandine) Pas d identification* KN2S4 red ruby Rubin KN2S5 red garnet, pyralspite group (mainly almandine) Pas d identification* KN2S6 Incolore, light grey diamont Weislochstein KN3S1 red ruby Rubin KN3S2 green emerald Smargd KN3S3 red ruby Rubin FN1S1 purple quartz, amethyst Amethyst FN1S2 green peridot (olivine) Smaragd FN1S3 purple quartz, amethyst Amethyst FN1S4 green peridot (olivine) Smaragd FN1S5 purple quartz, amethyst Amethyst FN1S6 green peridot (olivine) Smaragd FN2S1 green peridot (olivine) Smaragd FN2S2 orange garnet, ugrandite group (mainly grossular) Hyacinth FN2S3 green peridot (olivine) Smaragd FN2S4 orange garnet, ugrandite group ( mainly grossular) Hyacinth FN2S5 green peridot (olivine) Smaragd FN2S6 orange garnet, ugrandite group ( mainly grossular) Hyacinth Table 1: Results and identifications for the chalice s stones (1605). The numbering of stones of the Chalice 1605 starts at the Cremoser Granat, an imposing stone which is cracked in the middle, on the bowl. After, the numbering proceeds clockwise. The first character shows which part of the object, C for Bowl, K for Knop and F for Foot). The second character indicates the level and the third character indicates the stone. For example, Stone CN1S5, is in the bowl, at the first level, in the fifth position clockwise from the cremoneser granat. 6

7 Figures 1 to 2 Figure 1: Chalice of the Einsiedeln Abbey (1605) 7

8 Figure 2: Drawing by Father Eustache Tonassini, Inventary of the Einsiedeln Abbey s tresory ( ). 8

9 9

Agroup of four sacred objects belonging to the A STUDY OF THE GEMS IN A CIBORIUM FROM EINSIEDELN ABBEY. Rapid Communications

Agroup of four sacred objects belonging to the A STUDY OF THE GEMS IN A CIBORIUM FROM EINSIEDELN ABBEY. Rapid Communications Rapid Communications A STUDY OF THE GEMS IN A CIBORIUM FROM EINSIEDELN ABBEY Stefanos Karampelas, Marie Wörle, Katja Hunger, Hanspeter Lanz, Danilo Bersani, and Susy Gübelin The gemstones that adorn a