The Palette of the Medieval North

The selection of fragments contained many of those pigments already noted in the extensive analytical work conducted elsewhere in Europe7,8,9,10,11,12,13,14, such as azurite, red lead, vermilion, orpiment, and copper-based greens. Even though these fragment pages might appear rather simple in terms of their colour scheme, the analysis has shown a greater variation and complexity than first meets the eye. This observation will be further elaborated below where findings are listed by colour. A summary of the findings can be found in Table 2. Further images and XRF maps can be found in Supplementary information 2 (SI2), and 3 (SI3). Table 2 Summary of identified colourants and inks based on results from FTIR, Raman, HSI, FORS and XRF Full size table Blue All blues, except one, were identified as azurite by HSI (absorption max 640 nm) and FTIR (a strong doublet at 4380 and 4244 cm−1, which can be attributed to both the combination of ν + δ (OH) and the overtone 3ν3. This doublet partially overlaps with the methylenic C–H stretching and bending combination from lipidic binders), and is further corroborated by the presence of copper in the XRF analysis12,22. Azurite is a basic copper (II)-carbonate: 2 CuCO 3 ·Cu(OH) 2 forming bright blue crystals. The pigment can be prepared either from naturally occurring minerals or produced synthetically. The presence of particular impurities can arguably be used to attribute origin and identify leaves that come from the same workshop23. The azurites of the pages of the investigated selection show a variation in impurities, which could indicate different geological sources or different grades of purification. They showed the presence of barium, iron, zinc, arsenic, manganese and bismuth in XRF analysis with notable variability between the various fragments (Fig. 3, Table 2). The combination of impurities can thus confirm the likeness or not of the different fragments or various leaves of the same fragment. The presence of impurities in azurite has been noted in other analyses. For example, iron has been observed in 11th-century French manuscripts and zinc, arsenic, and barium in one 16th-century Flemish Book of Hours24. Barium, arsenic, zirconium, and bismuth were detected in two Italian manuscripts from the 13th and 15th centuries while antimony and silver were found in a 15th-century Spanish manuscript in synchrotron XRF analysis23. Fig. 3: Micrographs of azurite blues and their XRF spectra. Micrographs (a) of azurite blues of four fragments and XRF spectra of the blue areas shown in SI2 (b). Note variability in minor components such as manganese, barium, zinc, arsenic, and bismuth. Full size image Azurites are described as rendering varied colour hues depending on grain size16. The azurite blues of the selection show a variation of finely ground particles hardly discernible at ×80 magnification (Fr 4602 and Fr 10156) to a coarser grain size of ~20–40 µm in Fr 6638 and Fr 3814. The exception to the use of azurite was the blue writing in the 12th-century calendar fragment Fr 25621, which was identified as ultramarine with HSI, (absorption max 600 nm)12, and Raman spectroscopy (peak located at 545 cm−1 attributed to ʋ sym (S 3 −)25 (Fig. 4). Raman band at 1316 cm−1 indicates the possible presence of natural mineral such as diopside (CaMgSi 2 O 6 ), commonly associated with lapis lazuli in nature26, and suggests that transition metal dopants in the diopside may be responsible for the Raman features, likely the result of fluorescence with vibronic coupling27. Ultramarine is not an uncommon pigment used for manuscript colours. The source of natural ultramarine is the rock lapis lazuli, which contains a mixture of the minerals calcite, pyrite, and lazurite. The latter is a complex sulfur-containing sodium aluminium silicate, Na 6 Ca 2 (Al 6 Si 6 O 24 )S 2, which is the actual colouring agent of ultramarine28. This pigment has been found in many manuscript illuminations but was not so commonly used as ink to write text. However, blue text is quite often encountered in calendars. While the colour red was the most common one used to designate the most important saints29, blue was also used, at least in twelfth- and thirteenth-century manuscripts. Fig. 4: Photographs, Raman and HSI mean spectra of the blue ink of Fr 25621. Fragment 25621 (a, detail), a 12th-century calendar with blue text identified as ultramarine. b Microscopic view (×80 magnification), c Raman spectrum (exc.785) and d HSI mean spectrum (blue line, absorption max. 600 nm) with standard deviation (blue area) and ultramarine reference spectra (pure, in powder, dotted black line). Full size image Natural ultramarine is described as a precious pigment. The preciousness of ultramarine stems from the scarcity of known mineral sources for the lapis lazuli rock from which the pigment is obtained. Probable places of origin are Tajikistan, Pakistan, and Afghanistan26. It has been observed that there was a varying geographical and chronological use of different blues in the early medieval period, as azurite is more commonly found in Carolingian manuscripts, and ultramarine appears more often in Ottonian manuscripts and in early medieval England. In England, the use of azurite was not common until the 12th century9,10. The calendar fragment, Fr 25621, was produced in the late 12th century. The only Nordic saints in the original hand are Olav and Canute, which points to the calendar originating in the diocese of Linköping or possibly Denmark. Certainly, the manuscript was later adapted for use in the diocese of Linköping. As for ultramarine’s other applications in the Swedish context, the use of this pigment in contemporary Swedish wall paintings was not very common; it was only found in 10 out of the 70 analysed medieval church murals30. The blue text of Fr 25621 is also associated with the presence of lead, with lead white being confirmed by external reflectance FTIR (SI4_1), for the characteristic combination bands (CO 3 −2) at ca.1730 and 2400 cm−1 22. Red Not surprisingly, red is the most common colourant as it is used in rubrication. Out of 17,740 colour entries in the MPO database, 36% are listed as containing red, compared with 29% green, and 24% blue, while other colourants are below 10%. Most reds in the selection are identified as vermilion—the mineral cinnabar, HgS. Cinnabar was confirmed by Raman (main band 255 and 341 cm−1) for 28 out of 36 listed red and verified in HSI (inflection point at 600 nm) as well as indicated by the presence of mercury (XRF). The mineral cinnabar is usually associated with mercury mining in the Mediterranean, Central Asia, and the Pacific Ocean. Only a few places in the world have been historically relevant for its exploitation as a pigment, the known European ones being: Almadén (Spain), Idrija (Slovenia), Mount Amiata (Italy), Génépy (France), and Moschellandsberg (Germany)26. Hence, the presence of cinnabar in the analysed fragments constitutes evidence of material import. The term “vermilion” is used for the synthetic version of HgS, which, considering the period, is likely to be the one used in these fragments, and henceforth used for this red pigment. For some of these reds in initials and rubrication (in Fr 4602, 6638, 7285, 10411, 26692), lead was also detected by XRF indicating a mixture with a lead-based pigment. This was deduced to be red lead from the observation of characteristic peaks in Raman spectra (122, 391 and main 550 cm−1 due to stretching of the Pb(IV)–O-bond) of this pigment) and the lack of characteristic peaks for lead white in FTIR spectra, thus excluding the other common lead-containing pigment31. Mixtures of red lead and vermilion have been found in previous analyses of pigments in manuscripts10,14,16. Indeed, they are the most commonly encountered reds in the rubrication of medieval manuscripts. In fragments Fr 9451, parts of Fr 10411, Fr 10156, Fr 25621, and Fr 3814 (further discussed below) vermilion is the only red pigment present. In Fr 9451, the detection of sulfur in red areas is also associated with sulfate, as gypsum was indicated by HSI and FTIR (SI4_2). Calcite (sharp FTIR combination bands around 1800 cm−1; 2510 and shoulder 2594 cm−1), was also found in some reds used in Fr 10411 and Fr 26692 together with vermilion and it seems to have been used to adjust the hue (SI4_3 and 4). The exceptions to the mercury-based reds are the several reds of Fr 9635, where upon visual inspection, three to four different reds can be seen (Fig. 5, SI2_1 and 2). There is light red for the rubrication of ‘e’, ‘a’, and ‘F’ in the upper left corner and, the red text; the dark red initials ‘Q’, ‘D’, and smaller ‘C’, and then the medium red of large ‘C’ (top right). To map the distribution of the different reds, Spectral Angle Mapper (SAM) analysis has been performed taking into account the HSI spectra (in the range 450–970 nm) of the reds used for the capital letters (Fig. 5). The mapping shows that the light red used for the ‘F’, on the top left (in yellow in Fig. 5) was also used for part of the text. The dark red used for the ‘D’, in the left (in red in Fig. 5) was also used for the small ‘C’ and the ‘Q’ in the next column. Finally, the red used for the larger ‘C’ on the right (in magenta in Fig. 5) presents significant similarities with the light red spectra. The light red showed only lead in XRF analysis (SI2_1), suggesting the presence of red lead, also corroborated by Raman spectroscopy (characteristic bands at 120 and 550 cm−1) and by the HSI spectrum with an inflection point at 570/560 nm (Fig. 5) (SI4_8). Raman analysis also shows the presence of massicot in red text (with the presence of ulterior bands in addition to red lead at 140 and 288 cm−1)10,31,32. Fig. 5: Plot of HSI spectra and micrographs of the reds of Fr 9635 and their distribution. Plot of HSI spectra of the reds in the 450–970 nm range (b) and their distribution in the manuscript (a). a Light red pigment (yellow curve in b), medium red (in magenta), and dark red (in red) (b). Micrographs of light red ‘F’ (c), dark red ‘D’ (d) and medium red ‘C’ (e). Full size image Both lead and iron are present in the dark reds, and Raman analysis indicates a mixture with red lead. The presence of iron is stronger for the darker red ‘Q’ and ‘D’. The absorption maximum at 850 nm in the FORS spectrum in Fig. 5 is indicative of a red ochre7. Interestingly several other elements can be found in particles in the red ink of these letters, namely zinc, copper, and manganese (SI2_2). Particles containing mercury are also detected in the large ‘D’ (SI2_2). In the medium red capital ‘C’ XRF analysis detected particles containing zinc, copper and manganese similar to those seen in the dark red areas. The presence of impurities indicates a not very finely processed pigment. Fr 9635, which dates from the second half of the 12th century, is one of the earliest fragments identified as being of Swedish origin. It is thought to have been used in the diocese of Uppsala. A visually similar red, also containing copper particles, has been observed in the XRF analysis of a later Swedish law text, Östgötalagen MS B 50, dated to ~1325–1375 (personal communication Evans and Norrehed). Copper in the same mineral locality as iron is, for instance found in the Falun copper mine in central Sweden, where small-scale copper mining probably was practiced as early as in the 10th century33. Iron oxide, a by-product of copper mining, is known to have been used to produce a red paint, also containing copper vitriol. The pigment is made from heated haematite. In addition, Sweden has one of the earliest examples of the production of iron from iron ore, situated in Norberg in Bergslagen33. Another fragment, Fr 3814, showed a varied use of the reds in the Christ image: two hues of red appear in the drapery of the clothes, in Christ’s halo, and in the frame. Furthermore, there is the red of the wounds and a pinkish modelling of the body of Christ (SI2_3). From XRF scans, it is clear that vermilion has been used for the dark red shading of the drapery and the darker side of the frame, while the lighter red parts are vermilion mixed with red lead. The red for the rubrics and initials is also vermilion and red lead, a combination similar to that seen as common from the 12th century onward in British manuscripts9. In addition, XRF, FTIR and Raman analyses show that the hue of the light red of the clothes and drapery has been made lighter with calcium carbonate, which is also the main component for the flesh tones of Christ’s body. Most common flesh tones in medieval illuminations are lead white, often in combination with vermilion9, while here calcium carbonate is used as already documented in several examples9,10. For the wounds, only vermillion has been used. The pinkish brushstrokes modelling Christ’s body did not reveal any identifiable elements in XRF analysis, possibly indicating the use of an organic colourant as these were commonly employed in manuscripts for pink glazes10,34. This hypothesis of an organic colourant can neither be confirmed nor rejected here because while the shape of the reflectance spectrum did not have those of an anthraquinonic dye, a different organic red material cannot be ruled out (SI4_9). Green There were various colourants and pigments as well as their mixtures to render green colours in medieval manuscript production. Various copper compounds have been used, such as verdigris (a collective name for several copper acetates), copper sulfates and malachite, a basic copper carbonate. Often a mixture of a blue and a yellow has been used, for example, azurite and orpiment, or indigo and orpiment10. There are also entirely organic green colourants, such as sap green, that have been used10. More greyish hues are possibly given by green earth, a mixture of aluminosilicates of iron, magnesium, aluminium, and potassium (the colouring agent being a mineral such as celadonite or glauconite), but other minerals can be present. Green earth has been particularly connected to Byzantine and northern Italian manuscripts10. Green appears in six of the fragments examined in this study, showing a variation in hues ranging from dark to very light. All but one show copper in XRF analysis. In the analytical non-invasive investigation performed, it has not been possible to differentiate between the various copper-containing varieties. None of the greens shows clear spectral characteristics of malachite in FTIR, although bands of carbonate are observed. It is possible, however, to see the characteristic strikethrough on the other side of the parchment page normally associated with copper pigments for Fr 10156, the bright green of Fr 9635, the various greens of Fr 26692, 25621, and to a lesser extent, for Fr 4602. For 10156 and 26692 verdigris could be suggested by carboxylic stretching peaks possibly relative to basic copper acetate at 1556 and 1450 cm−1 (Fig. 6). For Fr 3814 it is not obvious, and there is no strikethrough for the dark green of Fr 9451 although FTIR also shows the presence of silicates in the 1000 cm−1 region (beyond parchment signals), not excluding the hypothesis of chrysocolla, a hydrous copper phyllosilicate35. The FTIR results for Fr 9451 also show a particularly strong presence of calcium oxalate (highlighted bands ca. 780 and 1610 cm−1)36 and an organic component of lipidic origin not excluding a wax given the characteristic inverted CH bands in the region 2930–2850 cm−1 37. Fig. 6: Photo- and micrograph of Fr 9451 and FTIR spectra of greens of Fr 9451, 26692 and 10156. Fr 9451 (a), micrograph (b) and FTIR spectra of the greens of Fr 10156, 26692 and 9451 (c). Dotted line indicate peaks for the presence of silicates for 9451 and 26692, and for carbonate for 10156 and 26692, asterisk show bands for calcium oxalate and arrows indicate carboxylic stretching peaks possibly related to basic copper acetate. Full size image Apart from copper being detected, other elements associated with the green are zinc in Fr 26692 and chlorine in the green of Fr 10156. Chlorine has been associated with a peculiar element of the salt used in the production process of the so-called ‘salt verdigris’, where copper is enclosed for a number of days coated with honey, salt, and vinegar38. It has been identified in the green colour of, for instance, a German illumination from the 16th century, and in some greens in the 12th century Bury Bible, from Bury St. Edmunds, England10. Verdigris, high in zinc, has been found in a gospel book from England possibly from the 11th century10. The only green not containing copper is the dull greyish green in the initials of Fr 9635 (small and big ‘A’, ‘D’, ‘p’ and ‘C’, SI2_4). The grey-green shows a clear presence of iron in combination with manganese, potassium, calcium and phosphorus (see SI2_5). FTIR suggests the presence of calcite, silicate, where in only one point, in small A, signals also of haematite can be observed (bands at 540 and 467 cm−1). The presence of iron, potassium and silicate could suggest the presence of green earth, but the diagnostic features of caledonite and glauconite were not observed by FTIR and no evidence for the presence of this pigment is seen in the vis-hyperspectral; at least not on the surface of the green shade. Whilst the presence of phosphorus could indicate a mix with bone black, the characteristic presence of bone black was not, however, observed by FTIR. Yellow Yellow is a less frequent colour on the leaves of these more text-dominated manuscripts. For this selection, yellow is found in five of the fragments. In our analysis, yellowish transparent layers, encountered in two manuscripts (Fr 26692 and Fr 9635, Fig. 7), have also been grouped together with more clearly yellow components. Usual yellows in medieval manuscript paintings are composed of arsenic sulfides such as orpiment, lead-tin yellow, or iron hydroxides (ochres). Organic colourants such as weld, safflower, saffron, and buckthorn were also used9,10. Evidence of these organic colourants was not observed with the non-invasive techniques applied in the present study. However, it was possible to note the strong co-presence of calcite in these areas, which may support the hypothesis of an organic yellow which could well have been absorbed or precipitated on calcite for the preparation of the pigment lake (Fig. 7a bands of calcite highlighted therein)39. Almost transparent layers are visible in Fr 26692 and 9635, in which no element but calcium can be determined by XRF, and no discerning identification could be made by the techniques utilized here. Fig. 7: Micrographs and FTIR spectra of yellowish transparent details. FTIR spectra (a) and micrographs of parts with yellowish transparent layers in Fr 26692 (b, d) and Fr 9635 (c). It is possible to note the co-presence of calcite in these areas which may support the hypothesis of an organic yellow. Full size image The yellows found in this selection range from bright yellow to almost all transparent. Fr 6638 shows an unusually bright and opaque yellow. This yellow was identified as orpiment because of the high scattering of arsenic sulfide compounds in the Raman analysis (main bands for orpiment- 152, 314, 355 cm−1) (Fig. 8) and arsenic clearly showing in the XRF scans (SI2_7)32,40. It is also possible to see particles of a more orange hue possibly indicating realgar (additional band Raman 270 cm−1) (Fig. 8). It is not uncommon for these arsenic sulfides to occur together. Orpiment was likewise identified in the yellow of the halos and Mary’s arm in the crucifixion scene of Fr 3814, and in the yellow flourishes of Fr 10411, all showing a more subdued colour than the yellow of Fr 6638. In the halos they are probably mixed with calcium carbonate, which was identified by FTIR and HSI, corroborated by a clear detection of calcium in XRF for this pictorial part (SI2_3). Fig. 8: Fr 6638, micrograph and Raman spectra of yellow. Yellow of Fr 6638 (a, b), identified as orpiment. Orange particles of possible realgar/pararealgar are seen in micrograph (b) and by Raman spectroscopy (c). Full size image Gold Gold can be seen in two of the objects, Fr 10411 and 3814, and its presence is verified with XRF (SI2_6 and 8). In Fr 3814, it is in the background of the image, the whole of it being most likely covered with gold on an earth-pigmented ground (SI2_8), as iron was also detected by XRF for this field. In Fr 10411 gold is in the dots of the decorated initial ‘S’ (SI2_6). In Fr 10411, the gold has a yellow base layer of orpiment. The use of orpiment together with gold has been noted in other studies9,14. In 12th-century English manuscripts, orpiment was used on top of gold9. Although it is tempting to speculate that the gold was added at a later stage due to the lack of precision, this conclusion is contradicted by the visible intermixing of the gold with orpiment. Black and brown, inks and flourishes For all but one of the included fragments, the main bodies of text showed a significant amount of iron in the XRF analysis, allowing the identification of iron gall ink, the exception being the brown ink of Fr 9635 (SI2_9). Furthermore, the infrared reflectance of the script of Fr 9635 was transparent, indicating it is not a carbon-based ink either. The brown colour could suggest a sepia ink; however, it has not been possible to see any indication of this in FTIR. The natural habitat of the source for making sepia ink is not found in close proximity to Scandinavia; however, imported ink is feasible. Nevertheless, it is more likely that it is a tannin ink without iron, i.e., a solution of plant extract from tree bark or gall nuts are known to have been brown in colour and being transparent in infrared reflectography from 750 nm41,42,43. This seems to indicate ink preparation taking place in circumstances in which iron sulfate (green vitriol) was not present. According to previous studies, carbon-based ink was often the preferred ink for drawing contours9,10, which is the function it has been used for in Fr 3814, shown in IR reflectance in SI2_11. It is also shown in the black flourishes of 10156 in IR reflectance (SI2_10). In Fr 26692, however, the outline of the figure of Jesus showed both iron and lead. Lead is not associated with iron, which can indicate the use of a lead stylus in sketching before applying the ink (SI2_11). The analyses make it possible to differentiate between different iron gall inks used in the same document. This can be seen in the IR reflectance image (SI2_11, b2), where the text next to the figure of Jesus in Fr 26692 is visible in IR reflectance while the other text is more transparent. In both texts, iron is detected in XRF analysis (SI2_11, b3). The visibility of the ink next to Jesus in infrared reflectance could suggest a mix of carbon-based ink and iron gall ink. Other instances of inks of different compositions in the same document can be seen in 10411, 6638 and 9635. In Fr 10411, an addition contains more copper than the main text, as shown by the false-colour XRF map where red is assigned to zinc and green to copper (Fig. 9e). Fr 6638 has an interlinear addition in different ink, and in Fr 9635 a different ink is seen for the musical notation. In the calendar of Fr 25261, there are visibly different black and brown inks, but it has been difficult to find any major differences between them in the analysis results. Only two brownish segments of iron are not visible in the XRF image (the writing below the red ‘Bartholomei’ and ‘augustini’ lower right, Fig. 4). It is possible that a greater resolution and a more precise Raman or more detailed infrared reflectance analysis up to above 1400 nm would be needed in order to differentiate these inks41,44. Fig. 9: Fr 10411, μ-XRF maps and false colour image of ink with interlinear addition. Visible-light image of Fr 10411 (a) and µ-XRF maps of ink with interlinear addition. The iron gall ink (map of iron, d) of the interlinear added text contains copper (b) while the original text contains zinc (c). e Shows a false colour image where red is zinc and green is copper. Full size image The analysis cannot only be used to verify different inks within the same document; it can also be applied to detect similarities in the composition of the used substances in different fragments. For instance, a very similar combination of elements other than iron can be detected by XRF in the iron gall inks used in Fr 10411 and 10156, i.e. zinc, potassium, calcium, and manganese. In order to group inks based on composition the ratio of impurities to iron could be used43. Although medieval Swedish written sources containing recipes are scarce, recipes for ink have been found in five manuscripts with a late-medieval provenance in the Bridgettine monastery of Vadstena45. In one manuscript, probably originally produced in Germany in about the 1430s, the production of iron gall ink is described. In this recipe, gall-nuts are placed in water with acetic acid in a copper pot, after which vitriol and gum arabic are then added46. This recipe is similar to others in common use at the time. The inks used for the headings of the taxation accounts from the 16th and 17th centuries often contain zinc, an element also detected in other iron gall inks of Scandinavian origin from the same period47. Binding media Interference from the parchment can make an interpretation challenging in FTIR, as protein bands of parchment can overlap with signals from suspected protein-based binders. Egg-based binders, namely, egg yolk, egg white, and whole egg produce complex spectra in external reflectance FTIR with variations influenced by the paint layer’s chemical and physical properties. The key chemical difference is that egg white is purely protein-based, while egg yolk and whole egg contain a lipid fraction. As a result, their spectra not only show the amide bands but also distinct lipid features. The presence of lipids is generally identified by a sharp C = O asymmetric stretching band, typically appearing between 1800 and 1700 cm−1 with a derivative-like shape, centred around 1740 cm−1, which in this case is covered by the amide signals of the parchment. It is at this point that instead in the NIR region that the combination bands ν + δ(CH), centred at 4399 and 4266 cm−1, are discernible in both pure egg yolk and whole egg binder systems11. Given such, it is difficult to diagnose proteins from egg white, which was a commonly used binding medium. Nevertheless, the fact that lipids could also simultaneously be detected in the NIR region in many colours could even indicate the use of whole egg as well as egg white as given, for instance, for the red of initial ‘S’ in Fr 10411 (SI4_3). In several fragments, oxalates could be seen by FTIR, which could be an indication of binding medium degradation. Observations on technique and divisions of labour Inks and initials In a scriptorium, there was often a division of labour among different specialized craftsmen with regards to copying the text, illuminating, and adding musical notation48. It has been suggested that this specialization was not very developed in Sweden49. In this study, it has become evident that inks of the same colour but with varied functions on the page often differ in composition. In our interpretation, the variation in the inks suggests a division of labour. While the possibility that the same craftsperson used different raw materials for different inks during various stages of book production of the page, such as copying the text and decorating, cannot be completely ruled out, this appears the most simple reading of the evidence. Some examples of these variations are described below. For Fr 10411, the blues of the minor initials in the text and the blue of the major initial ‘S’ show a different composition in regard of barium content in relation to copper, barium being more abundant in the ‘I’ (Fig.10), possibly suggesting the use of different azurite batches. Although impurities like arsenic and zinc are present in all the letters painted in azurite, the scatter plot (d) in Fig. 10 gives evidence of two different correlations between barium and copper for the two blue initials. This result possibly implies the use of two different azurite batches. Analogously, in Smieska et al. the study of the ratio of barium to copper showed the use of at least four types of azurite on the same manuscript page and the authors suggested that this is the result of a use of different natural sources of azurite, or of a purification process23. Fig. 10: Differentiation between the blues in Fr 10411. The flourishes and initials ‘I’ and ‘Q’ is in green square and the blue of the decorated initial ‘S’ is in yellow square. Comparison of the VIS-light image (a) and MA-XRF results: maps of barium (b) and copper (c), false-colour scatter image (e) from the scatter plot in (d) representing areas where these elements correlate, and Ba content is lower (yellow) or higher (green). Full size image Fr 10411 also has reds with different compositions. Vermillion with red lead was used for the red of the initials and for rubrication, while for the decorated ‘S’ initial only vermilion was used, possibly in a mixture with calcium carbonate, as indicated by FTIR (SI4_3), and calcium is evident in XRF mapping. Musical notation There is a musical notation in three of the selected fragments. They are a gradual responsorial for Christmas (Fr 7285), a processional antiphon for Easter (Fr 9635) and an invitatory for Palm Sunday (Fr 10156). In addition, there are stave lines without notation in Fr 3814. For Fr 10156 and Fr 7285, the results do not show any evident differences between substances used for the notation and text elements. As mentioned above and visible to the eye, the colour of the notation and text of Fr 9635 is different. All of the stave lines, apart from that of Fr 9635 are red in colour, with results showing vermilion and red lead for all reds apart from that of Fr 10156, in which only vermilion is present. The stave lines of Fr 9635 are brown but do not provide the same results as with the brown text, since lead is detected in the XRF imaging (SI2_12). This could indicate the use of brown earth or could possibly be traces of some sketching with a lead stylus. In addition, in Fr 9635, the notes of the music show a different reflectance in IR than the stave lines and the text. Ruling For all but one page of the two analysed pages of Fr 9635, ruling is visible on visual inspection to a greater or lesser extent, and most clearly so in Fr 9451 and Fr 7285. For three of the fragments (Fr 7285, Fr 3814 and Fr 10411) iron gall ink is indicated as the lines, either all or partly, show iron in XRF imaging. A use of lead is indicated for Fr 26692 which is consistent with the possible use of lead stylus for the contour of Christ. Interestingly, one side of Fr 9635 shows the ruling while the other side does not. The page with the ruling has been ruled with a metal instrument and lead is seen in the µ-XRF map (SI2_5). On one side, the trace of this instrument is visible, and on the other only, the indentation. The use of a metal tool for ruling was standard practice in the 12th century. For the other fragments, no conclusive results have been obtained. It can, however, be noted that the ruling seen in Fr 10156 is semi-transparent upon visual inspection, and possibly made by indentation.