Sebastian Bosch*, Andreas Janke Manuscript Illumination in

Open Information Science 2021; 5: 63–88

Research Article

Sebastian Bosch*, Andreas Janke

Manuscript Illumination in 19th-century Italy. Material Analysis of Two Partial Copies from the Squarcialupi Codex

Open Access. © 2021 Sebastian Bosch, Andreas Janke, published by De Gruyter. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

https://doi.org/10.1515/opis-2021-0006 received August 14, 2020; accepted March 3, 2021.

Abstract: The illuminations in two Italian manuscripts are still a mystery today. Both manuscripts were based fully or partly on the Florentine Squarcialupi Codex (Florence, Biblioteca Medicea Laurenziana, Med. Pal. 87) dating from around 1410/15. With the help of a multi-analytical, non-destructive approach employing mobile instrumentation (XRF spectroscopy, visible reflectance spectroscopy and infrared reflectography), we examined the manuscripts Toronto, Thomas Fisher Rare Book Library, MSS 09700 and Düsseldorf, Kunstpalast, Inv. K 1925-67 for the first time with regard to their production processes. The identification of modern pigments allows them to be contextualized in illumination practices of the 19th century. Manuals of that time provide a wealth of information on specific illumination practices and the availability of writing and painting materials, which correlates with the actual artefacts.

Keywords: artefact profiling; ink and pigment identification; XRF spectroscopy; infrared reflectography; visible reflectance spectroscopy.

1 IntroductionArchives and libraries house countless illuminated manuscripts that have not been sufficiently examined to date and often little is known about their origin and history. This situation is particularly difficult for illuminated manuscripts whose dating is so uncertain that their creation is sometimes dated to the Middle Ages and sometimes to the 18th or 19th century.

This study focuses on two such items that could not be more different, it seems initially. Case study I examines a manuscript called Toronto, Thomas Fisher Rare Book Library, MSS 09700 (the Fisher Antiphonary) – the complete manuscript has been digitized and is accessible online (https://collections.library.utoronto.ca/view/fisher2:F6521). This is a liturgical manuscript (with musical notation) that was conceived in the late 15th century or at the beginning of the 16th century at the latest. At a subsequent point in time, it received a completely new decoration system, the context of which has not yet been fully understood. Previous research projects may have been hindered by the fact that the quality of the illuminations does not appear to be very professional in several respects (see fig. 1). However, this cannot be a legitimate reason for the lack of research as several painters were clearly at work in this case. The parts of the manuscript’s history that are still unknown consequently need to be investigated if this manuscript is not to be treated solely as a largely “history-less” curiosity.

Case Study II examines the hitherto unknown fragment Düsseldorf, Kunstpalast, Inv. K 1925-67 (the Düsseldorf Fragment), which in contrast to the illumination in the Fisher Antiphonary was created by a much more professional illuminator (see fig. 2). Despite these substantial differences, both manuscripts share the significant quality that they are full or partial copies from a Florentine music manuscript from the first few decades of the 15th century: the Squarcialupi

*Corresponding author: Sebastian Bosch, University of Hamburg, Germany, E-mail: [email protected] Andreas Janke, University of Hamburg, Germany

https://collections.library.utoronto.ca/view/fisher2:F6521

64 Sebastian Bosch, Andreas Janke

Figure 1: Toronto, Thomas Fisher Rare Book Library, MSS 09700 (Fisher Antiphonary), fol. 1r. Reproduced by permission.

Figure 2: Düsseldorf, Kunstpalast, Graphische Sammlung, Inv. K 1925–67 (Düsseldorf Fragment). Reproduced by permission. Photo by Horst Kolberg / ARTOTHEK.

Manuscript Illumination in 19th-century Italy. Material Analysis of Two Partial Copies from the Squarcialupi Codex 65

Codex (or Sq for short): Florence, Biblioteca Medicea Laurenziana, Med. Pal. 87 (fig. 3). This is especially known among musicians and musicologists as it contains 352 secular songs. The entire manuscript has been published as a facsimile (Gallo 1992). The manuscript’s contents are divided according to composers. Each section on a composer begins with an elaborately illuminated page. The respective composer is represented by a historiated initial, as shown in fig. 3, which depicts the blind organist Francesco Landini (c.1335–1397). Besides having marginal decorations, there is also a bas-de-page miniature referring to the text of the composition written on that page – in our example, it is the personification of music referring to the madrigal entitled Musica son che mi dolgo, piagendo. This is a unique decoration system, the most important elements of which appear here for the first time, unlike in many choir books, whose illumination was often based on models that can be traced back a considerable amount of time.

This paper presents a detailed scientific analysis with the main objective of dating the illuminations of the Fisher Antiphonary and the Düsseldorf Fragment verifiably within a certain period of time, thus providing a reliable basis for further examination of these particular manuscripts and those of a similar nature. As a basis, we used analytical data which we obtained on site in Toronto (Canada) in 2018 and in Düsseldorf (Germany) in 2019 using CSMC’s ‘Mobile Lab’ equipment.

Figure 3: Florence, Biblioteca Medicea Laurenziana, Med. Pal. 87 (Sq), fol. 121v. Reproduced by permission of the Ministero della cultura. Any further reproduction by any means whatsoever is prohibited.


Scientific methods serve to identify the writing and painting materials used to produce and enhance the manuscripts. These insights are crucial to clarify unresolved questions regarding the production processes of such cultural artefacts. It is widely accepted that the use of writing and painting materials changes in relation to their purpose, place and time of use, depending on factors such as price, value and availability. In particular, the discovery of new chemical elements and compounds as well as the growing production of modern pigments and dyes influenced artists’ palettes. Identifying these materials often provides clear indications of the history of manuscripts.

In the following, we will briefly describe all the scientific methods that were employed. Each manuscript will then be analysed separately. Relevant information on the history of the manuscripts is also provided, but it is mainly limited to previously unknown details that we were able to find out in the course of our research. A detailed presentation of the analysis of all our measurement data follows, the focus being on those aspects that allowed us to narrow down the date range when the illuminations were created. All the datasets we analysed in this study are available online for further research (http://doi.org/10.25592/uhhfdm.1419; http://doi.org/10.25592/uhhfdm.1421).

As we shall demonstrate, the illumination in both manuscripts cannot be dated to before the 19th century. Our results will therefore also be placed in the larger context of 19th-century manuscript illumination, which has mainly been discussed so far for Great Britain, France and Belgium (e.g. in Hindman & Rowe 2001, and Coomans & Maeyer 2007). However, the manuscripts examined here most certainly come from Italy and were probably both made in Florence. The main reason for this assumption is Sq, the model that was already kept in the Florentine Laurentian Library in the 19th century. In comparison to manuscript illumination in Great Britain and France in particular, manuscript illumination in Italy has received little attention so far, although the publications by Labriola (2016), Guernelli (2011) and Ascoli (2007) should be mentioned here as important exceptions. Hence, our study is also a contribution to the analysis and contextualization of such manuscripts from Italy in the 19th century. It will allow to further analyse in detail the question on the relationship between original manuscripts and their copies (Janke, in preparation).

This study brings together the interests of the natural sciences and the humanities, an approach also represented by the disciplinary background of the authors themselves. Since the Fisher Antiphonary and the Düsseldorf Fragment are representative of a number of other similar artifacts, all of which had Sq as a model, it is this study that will allow future research on these and similar objects to be given an objective basis.

2 MethodsOur scientific data is mainly based on X-ray fluorescence spectroscopy (XRF). In general, this method allows the elemental composition of materials to be determined and in most cases pigments and metals to be identified. Mobile XRF instruments are limited in the detection of light elements (atomic number Z<11) and thus are not suitable for identifying organic dyes and certain inorganic pigments. We have therefore included visible reflectance spectroscopy (VIS) here. This method provides additional information about the spectral behaviour of a material under visible light, and when used together with XRF data, it enables inorganic and organic colourants to be identified. Finally, we employed infrared reflectography (IRR) to determine what black inks were used for outlining the illuminations and for script and musical notation. Some surprising results appeared in Case Study II, which were initially obtained with a simple USB microscope and prompted us to image the entire fragment with a state-of-the-art infrared reflectography camera in a second measurement campaign. Our mobile instruments can only analyse local areas of objects, depending on the size of the measuring point (XRF and VIS) or the field of view (IRR). For this reason, several measurements were taken at different points on the writing and painting material to prevent misinterpretation. All of the methods we employed are non-invasive and non-destructive.

2.1 X-ray fluorescence spectroscopy (XRF)

XRF spectra were recorded with ELIO®, a portable energy-dispersive spectrometer from XGLab S.R.L., Italy. This compact system consists of an air-cooled, low power rhodium anode serving as an excitation source, a large-area silicon drift detector (SDD, 25 mm2) and a microscope camera for easy object positioning. The excitation X-ray beam is collimated

http://doi.org/10.25592/uhhfdm.1419



to a point diameter of 1.2 mm on the sample surface. The XRF measurements were carried out at 40 kV and 20 µA with a detection time of 240 s. Each available ink, colourant and metal was measured at no less then three different spots. For reference purposes, the same thing applied for the parchment writing support. The raw data collected was further evaluated with Spectra, ARTAX 7.2.5.0 (software from Bruker Nano GmbH, Germany). By deconvolution of the measured XRF spectra, we obtained net peak intensities which were used to calculate relative intensity ratios.

2.2 Visible reflectance spectroscopy (VIS)

The colourants were further examined with an eXact spectrophotometer (X-rite GmbH, Germany). This handheld device illuminates the measuring point at an angle of 45 degrees for less than a second using a small 2-Watt light bulb. The light reflected from the object’s surface is then detected by a sensor. The resulting reflection spectrum can be compared with reference spectra to identify the colourant. The collected reflectance data was further converted into first-derivative and Kubelka-Munk spectra to show inflection points and characteristic absorption features of the dyes. Spectra were recorded at the same locations for each technique in order to be able to compare this data with the results of the XRF analysis.

2.3 Infrared reflectography (IRR)

The reflectance behaviour of the black inks was first examined with a three-colour imaging USB microscope (Dino-lite AD413T-I2V, Metav, Germany) to differentiate between possible black ink types. The microscope offers the possibility to acquire images with magnifications from ×50 to ×200 under ultraviolet (UV, 390 nm), visible (VIS) and near-infrared light (NIR, 940 nm). The field of view is a few centimetres. For case study II, we conducted a second measurement campaign with an Apollo reflectography camera (Opus Instruments, UK) to capture the whole fragment. With an electronically cooled InGaAs area sensor (128 × 128 px), the camera can capture the reflectance in a wavelength region of 900–1700 nm and returns 16-bit images (up to 26 MP, 128 × 128). As an external light source, we used a purpose-built Illumination Kit (Opus Instruments, UK), which mounts directly onto the camera lens rods. It consists of two dimmable halogen bulbs (20 W) mounted on flexible arms, which allows for optimized lighting conditions. Furthermore, we used a Filter Set (Opus Instruments, UK) with three attachable filters (a 1250 Short Wave Pass filter, 1250–1510 Band Pass filter and 1510 Long Wave Pass filter) to increase the spectral sensitivity of the materials that were present.

3 Case study I: Toronto, Thomas Fisher Rare Book Library, MSS 09700The late director of the Thomas Fisher Rare Book Library, Richard Landon (1941–2011), loved to announce the manuscript analysed here in case study I as “the ugliest book in our library” when showing this huge manuscript (approx. 600 × 450 mm in size) to students or visitors (see fig. 1).1 The manuscript with the shelf number MSS 09700 has two different qualities: if the enormous antiphonary with its illuminations is seen from a distance, it appears to be something special and precious, but the closer one gets to the manuscript itself, the more doubts and questions arise. Twenty-two historiated initials and bas-de-page miniatures were painted over the text and music in a 15th- or early 16th-century antiphonary from Italy without any relation to the original contents, but leaving the rest of the manuscript intact.

The card catalogue of the Royal Ontario Museum in Toronto contains valuable information on the recent history of the manuscript. For one thing, the antiphonary has been owned by the Museum ever since September 1909. It was purchased from the well-known book dealer Wilfrid Michael Voynich (1864–1930). Later, in 1964, it was transferred to the Thomas Fisher Rare Book Library and thus reached its current location.

1 We thank Pearce J. Carefoot for sharing this anecdote with us.


It was already pointed out in the card catalogue that some of the illuminations are based on well-known Florentine works of art from the 15th century, e.g. on fol. 57v one of the three magi from Gentile da Fabriano’s Strozzi altarpiece Adoration of the Magi (Florence, Uffizi Galleries) has been copied into the Antiphonary and put in an initial “M”. There is an angel from one of Benozzo Gozzoli’s frescoes in the Medici-Riccardi Palace that now inhabits an initial “P” on fol. 139r, and Mary from Fra Filippo Lippi’s Adoration of the Child (originally from the convent of Annalena in Florence, now in the Uffizi Galleries) is depicted in an initial “P” (fol. 69r).

In the accompanying catalogue to “Fiat Lux – An Exhibition of Mediaeval Manuscripts and Early Printed Books in the Fisher Library” in 1994, a reference to Sq was made (probably for the first time), which obviously served as a model for most of the illuminations in the Antiphonary (Josz 1994).

Thanks to Ilana Krug’s 2013 article, the manuscript was finally made known to a wider audience. She dated the later illumination to between 1469 and 1494 and suggested that the new illumination was part of a political agenda between the Florentine families of the Strozzi and the Medici. However, the poor quality of the illuminations (which is certainly not good enough to make the manuscript a gift between the two families) and the appearance of further (partial) copies of Sq (see case study II) raised doubts about her analysis. Many felt hesitant about her dating, suspecting that the illuminations were added much later. The musicologist Michael Cuthbert, for example, was able to express this in a convincing example and kindly shared this finding with us (personal communication, July 2017). He noticed that two of the figures copied from Sq were holding a book with music notation in their hands (on fols. 31v and 51v), with some beamed notes, a characteristic that cannot be connected in any way with the period proposed by Krug.

Based on the liturgical contents, a recent study proposed the compelling thesis that the antiphonary originally came from Northern Italy, was made in the 15th or early 16th century and belonged to the Franciscans, who used the manuscript for a very long time, possibly until the 18th century (Piazza 2019). The card catalogue only indicates the provenance of the manuscript as “probably Florentine”. This educated guess may not only be based on the Florentine motifs in the illumination, as the manuscript was presumably acquired in the city on the Arno as well.

Voynich started his career as an antiquarian book dealer in London in 1898 and made regular buying trips to the Continent, mainly to Italy. However, it was not until 1905 that he started to trade in manuscripts. In 1908 he bought an entire bookshop in Florence called Libreria Franceschini (Hunt 2016). This was certainly not an ordinary place, but had been shaped by its eccentric previous owner, Pietro Franceschini. The British writer and translator Helen Zimmern described him as follows (Zimmern 1908):

He knew little and cared less about quality. It was quantity that seemed to attract him. He was a bibliomaniac rather than a bibliophile … He piled his purchases on the shelves till they were laden to breaking-point. Then he filled the floor. When that was too crowded … he flung his wares into a dark room some 20 feet high and 15 feet wide.

After becoming the owner of Libreria Franceschini, Voynich began to sort the books and manuscripts with the help of his assistants. Already in April 1908 he published a specific list of 352 books connected to the city of Florence and the Florentines (Voynich 1908). Unfortunately, no manuscripts are listed in it. It is very likely that the Fisher Antiphonary was part of Libreria Franceschini when Voynich took over the shop. The book dealer obviously did not think much of the manuscript, as he sold it – according to the card catalogue – for only £30. This is comparatively little since he sold a single illuminated parchment leaf to the British Library for £75 in 1905. This was a work by the so-called ‘Spanish Forger’, which is now kept in the British Library (Add MS 37177). The pricing mainly seemed to be due to the quality of the illuminations. With regard to complete manuscripts, Voynich later distinguished between ‘trade manuscripts’, which he sold for between £400 and £800, and ‘fine manuscripts’, which were reserved for renowned collectors (Hunt 2016).

We can therefore assume the terminus ante quem for the illuminations in the manuscript was 1908. In the following, the illumination in the Fisher Antiphonary is examined on the basis of a scientific analysis for the first time. We will show that the terminus post quem for the illumination of the manuscript is certain to have been the second half of the 19th century.

The scientific results from X-ray fluorescence (XRF) and visible reflectance (VIS) measurements are summarized in Table 1. The data allows an assignment of the materials used for the script and musical notation of the original Antiphonary (the first layer) and for the illumination added later (the second layer). A detailed discussion is given below.


Table 1: Writing and painting materials used in the Fisher Antiphonary and identified by XRF and VIS. For the colourants, only the elements are listed that were detected in addition to those from the white admixture (Zn, Ba and S). a reflectance maximum, b inflection point (first derivative spectrum), c absorption features (Kubelka-Munk). References for the assignment of materials and their availability/first date of production as a pigment are given in the text.

Analysed areas XRF (elements) VIS (nm) Material assignment Availability

First layer – script and musical notation

red Hg, S 600b vermillion since antiquity

blue Cu 460a, 500b, 630c azurite since antiquity

black Fe, Cu, Zn -- iron-gall ink since antiquity

Second layer – illumination added later

white Zn -- zinc white 1834

white (ground) Ca, S -- gypsum since antiquity

white (admixture) Zn, Ba, S -- zinc white, baryte 1834, 1793

orange Pb 580b red lead since antiquity

red Pb 600b, 500c, 525c madder lake,red lead

since antiquitysince antiquity

pink -- 600b, 520c, 560c crimson lake/carmine since antiquity

purple -- 590b, 520c, 560c,625c crimson lake/carmine,artificial ultramarine

since antiquity1828

blue -- 590b, 520c, 560c, 625c artificial ultramarine 1828

yellow Cr 510b zinc/lemon yellow 1847

green Cr, Fe 500b viridian 1859

black -- -- carbon ink since antiquity

gold (fols. 1r–12v) Au, Fe, Ca, Sr 510b gold leaf since antiquity

gold (fols. 12v–end) Cu, Zn, Fe, Ca, Sr 540b brass leaf/paint since antiquity

3.1 Scientific results

3.1.1 White pigments

For the illuminations added later, the results of the XRF measurements (figs. 4d–e) allow the identification of two types of white pigments that were used for different purposes when painting. The white opaque areas (figs. 4a–c) show strong signals for zinc (Zn) and can be assigned to the pigment known as zinc white (zinc oxide, ZnO). In contrast, the white background of the coat of arms (fig. 4c) shows signals for calcium (Ca) and sulphur (S) and can be assigned to gypsum (calcium sulphate dihydrate, Ca[SO4]·2H2O). The calcium signals of the parchment are only half as intense and in this case originate from the collagen in the animal hide and/or from materials used in the production of the parchment, such as lime for priming. Interestingly, the parchment also contains a relatively high amount of strontium (Sr), which can be absorbed in the animal hide in a similar way to calcium. In addition, it may have remained as an impurity during the parchment’s processing and could indicate the use of gypsum (Franceschi & Locardi, 2014). To the best of our knowledge, however, no study has been made yet of the relative amounts of strontium in different writing supports. In the future, however, findings of this kind should be compared to try to pinpoint their origin.

Compared to the reference measurement of the parchment, the sulphur signals for the white backgrounds are significantly high. This is further illustrated in fig. 4e for all the measurements of the white areas and parchment. The


right-hand side of the figure (Zn/Ca > 1, with Zn as the primary XRF signal) shows the results of the white opaque areas painted with zinc white, while the left-hand side (Zn/Ca < 1, with Ca as the primary XRF signal) shows the results of the white areas of the coat of arms and the references measured on parchment. In the former case, we were able to detect a higher sulphur content (S/Zn > 0.1), which is due to the use of gypsum, a white pigment known since ancient times (Gettens, West Fitzhugh & Feller, 1993). In contrast, zinc white is a modern pigment that was not part of an artist’s palette before 1834 (Kühn, 1986). In this study, it therefore serves as the first reliable indication that the illumination of the Fisher Antiphonary was not added before the 19th century.

3.1.2 Colourants

Seven different colours can be distinguished in the illumination added later: red, orange, yellow, green, blue, purple and pink. Their opacity is high enough to cover the writing and music notation in the original antiphonary (i.e. the first layer). Such high colour strength can be achieved by mixing the colourants with an opaque white pigment such as zinc white. In fact, the XRF results clearly show that zinc is one of the primary signals for all the colours analysed (fig. 5a),

Figure 4: XRF results of the white pigments used for the Fisher Antiphonary. (a–c) Details of white areas which were identified as zinc white (light-grey circles) and gypsum (dark-grey circle). (d) Exemplary XRF spectra of the white areas and the parchment showing the main detected signals of zinc (Zn), calcium (Ca), sulphur (S) and strontium (Sr). Spectra are normalized to the highest signal. (e) Scatter plot of intensity ratios S/Ca vs. Zn/Ca for all measurements on the white areas and the parchment.


thus suggesting that zinc white was also used as an admixture in the colourants. However, all of the measurements showed weak barium (Ba) and sulphur (S) signals as well, which indicates that the colourants were mixed with lithopone (BaSO4 + ZnS) or with a mixture of zinc white (zinc oxide, ZnO) and baryte (barium sulphate, BaSO4). Unfortunately, XRF measurements cannot directly distinguish between these admixtures as they show the same signals (Zn, Ba and S) in the spectra. However, Figure 5b shows a high scattering of the Ba/Zn intensity ratios (0.001-0.472), which would not be expected when using lithopone (a prefabricated pigment with a fixed element composition). We can assume that the colourants were mixed with different amounts of zinc white and baryte for this reason. The latter has been known as a typical filler material ever since the beginning of the 19th century (Feller, 1986).

In addition to the detected admixtures, the XRF spectra of the colourants show some other characteristic signals which can be assigned to specific pigments in most cases. Since there are no significant changes in the XRF and visible reflectance data between measurement points within the same colourant, we can conclude that the illuminators used the same colour palette throughout the manuscript and achieved differences in hue by simply adjusting the amount of colourant and the admixture mentioned above. The spectra from XRF (fig. 5a) and VIS (fig. 6 and fig. 7) are therefore representative of all measurements of the respective coloured areas.

Figure 5: XRF results of the colourants used for the illuminations in the Fisher Antiphonary (orange, red, pink, purple, blue, yellow, green). (a) Exemplary XRF spectra normalized to their highest signal in the low (left) and high (right) energy region. The asterisk marks the signal of argon detected in the air. (b–c) Respective scatter plots of all the collected XRF data showing the relative amount of barium (Ba/Zn) and chromium (Cr/Zn).


In the case of orange and red, the XRF results (fig. 5a) show strong lead (Pb) signals, which can be attributed to red lead (lead oxide, Pb3O4). In the orange areas this is further confirmed by the results of the VIS data (fig. 6a), which show an inflection point at 580 nm (Oltrogge, 2008). In contrast, the red areas have an inflection point at 600 nm. This suggests that a layer of red lead was applied first, which was then painted over with a red organic dye or lake that is not detectable with XRF. However, it is possible to determine the nature of these colourants from the converted VIS data (Kubelka-Munk spectra), which is shown in Figure 6b. The absorption maxima at 500 and 525 nm for the red areas indicate the use of a vegetable madder lake, while the maxima at 520 and 560 nm for the pink and purple illumination areas can rather be assigned to an insect dye such as kermes or cochineal (Aceto et al., 2014). Pigments from the latter dyes are called crimson lake or carmine.

The additional maximum at 630 nm for the purple areas is attributed to the blue colourant in this pigment mixture and can also be determined for the blue areas of the illuminations, which is characteristic of two pigments, azurite and ultramarine (Mounier & Daniel, 2017). Since the XRF spectra from both colourants show no signal for copper (Cu), we can exclude azurite (Cu3(CO3)2(OH)2) beyond any doubt and thus identify the blue pigment as a type of ultramarine. For the blue areas of the illumination, this can be further confirmed by the reflection maximum at 450 nm. These results indicate the use of an artificial ultramarine (Aceto et al., 2013), which very quickly replaced the natural pigment obtained from the expensive mineral lapis lazuli from 1828 onwards (Plesters, 1993).

More proof of the modern illumination of the Fisher Antiphonary can be seen in the presence of chromium (Cr) signals in the XRF spectra of the green and yellow areas (fig. 5a). These have a relatively high intensity compared to the other colourants (fig. 5b) and are therefore attributed to the use of chromium pigments, which have only been available since the middle of the 19th century. After the discovery of chromium as an element in 1797, it took more than 30 years until the green pigment known as chrome oxide green was produced as an artist’s material in 1838 (Newman, 1997). It was mainly sold as viridian (hydrated chromium(III) oxide, Cr2O3·2H2O). At the same time, several yellow chromates of barium, strontium, lead and zinc were developed. In this case study, however, the XRF data does not guarantee their reliable identification. On the one hand, the green areas can consist of either a chromium oxide pigment or a mixture of yellow chromate with a blue colourant. Furthermore, the detected signals for barium (Ba), zinc (Zn) and strontium (Sr) can also originate from the white admixtures or from the parchment and therefore cannot be assigned to a specific yellow chromate. Due to the absence of lead, we can only exclude the use of lead chromate. However, the inflection point at 510 nm (fig. 7b) indicates that the yellow illuminations consist of zinc or lemon yellow (Otero et al., 2017), a zinc potassium chromate (4ZnCrO4·K2O·3H2O) which was only produced as an artist’s pigment in 1847 (Kühn & Curran, 1986).

Figure 6: Visible reflectance data collected from the coloured illuminations of the Fisher Antiphonary. (a) Exemplary first derivative spectra of the orange and red areas. (b) Exemplary Kubelka-Munk spectra of the red, pink, purple and blue areas. All spectra are normalized.


The green areas show a reflection maximum at 500 nm (fig. 7a), which indicates the use of viridian in conjunction with the features of the first derivative (fig. 7b) (Oltrogge, 2008). Based on these findings, the iron (Fe) signal additionally detected is more likely to come from impurities since the VIS data rules out the presence of iron-containing pigments such as green earth or Prussian blue. Finally, zinc yellow and viridian serve as two further marker pigments that date the later illuminations to the middle of the 19th century at the earliest.

Subsequently, the identified colourants in the later illumination were compared with the materials used for the original antiphonary (first layer). Clear differences can be determined by XRF measurements in particular. We only detected strong copper signals in the blue areas of the first-layer initials (e.g. the “T” initial in fig. 1), which can only come from the blue pigment azurite (basic copper carbonate, Cu3(CO3)2(OH)2), while all the red areas of the original antiphonary (the initials, rubrics and stave lines) produced characteristic mercury (Hg) and sulphur (S) signals, which can only arise from the red pigment vermillion (mercury sulphide, HgS). Both azurite (Gettens & West Fitzhugh, 1993) and vermillion (Gettens, Feller & Chase, 1993) have been known since ancient times and were widely used for writing and painting purposes until the development of new synthetic alternatives. Further differences could also be determined in the case of the black inks used for the original antiphonary and the illuminations. The detection of iron (Fe), copper (Cu) and zinc (Zn) signals for the musical notation and script clearly showed the presence of iron-gall inks. In contrast, the black outlines of the illuminations did not exhibit any of these signals and must therefore come from either plant or carbon-based inks only containing light elements which cannot be detected by XRF. Further information about the types of black ink used can be obtained by infrared reflectography (IRR). The images in figure 8 clearly show that iron-gall inks were used for the original antiphonary (musical notation, figs. 8a–c; and script, figs. 8d–f) since they lose opacity under illumination at 940 nm (Rabin, Hahn & Binetti, 2014). In contrast, the black outlines of the illuminations added later (figs. 8g–i) remain unchanged and can thus be clearly assigned to carbon-based inks (Mrusek, Fuchs & Oltrogge, 1995). Both types of ink were already standard in the Middle Ages, and iron-gall ink only became obsolete in the 20th century (Zerdoun Bat-Yehoudan, 1983). As a result, their detection does not provide any additional help in dating this manuscript. Although it is possible to distinguish different iron-gall inks on the basis of a fingerprint model (Malzer, Hahn & Kanngiesser, 2004), this would have required a widely distributed number of measuring points, which was beyond the scope of this work.

Figure 7: Visible reflectance data collected from the coloured illuminations of the Fisher Antiphonary. (a) Exemplary reflectance spectra of the blue, yellow and green areas, and (b) their exemplary first derivative curves. All spectra are normalized.


3.1.3 Gold and brass

Illuminated manuscripts were often decorated with gold. However, this precious metal was expensive and cheaper alternatives such as brass were also employed. In the Fisher Antiphonary we were able to detect the use of both materials. Our XRF measurements clearly showed the presence of gold (fig. 9a) in all the gilded areas on fol. 1r, such as the buds in the decorated boarders (fig. 9c) and the halos (fig. 9e). It was also used for the background of the Medici coat of arms on folio 12v (fig. 9g). Interestingly, all the other metallic areas from folio 12v to the end of the manuscript do not contain gold, but mainly produced copper (Cu) and zinc (Zn) signals, which means they can be assigned to the metal alloy brass (fig. 9b). These results were confirmed by our VIS data, which shows typical inflection points at 510 and 540 nm characteristic of gold and brass respectively (Aceto et al., 2013). Moreover, strong variations in the Cu/Zn ratio were determined. Additionally, clear differences could be seen in the microscopic images of the XRF instrument. In some places, a raised white to reddish or brownish layer could be seen underneath all the decoration with gold as well as brass buds (fig. 9d), which is a strong indication that these areas were decorated with metal leaves over a preparatory layer. The coherent metallic surfaces and the striations resulting from the polishing also confirm this. The detection of iron (Fe) and strong calcium (Ca) signals in the XRF measurements (figs. 9a and 9b) further suggests that an earth-coloured bole of iron pigments and gypsum was used as a common preparatory layer (Fuchs, 2018). In contrast, the brass halos (fig. 9f) and coat of arms (fig. 9h) have a rather particulate texture and the absence of a ground layer, which illustrates the use of brass paint. These areas have lower Cu/Zn ratios as well (fig. 9b), which point to different types and qualities of brass. It should be noted, however, that the Zn signals may have been higher because of the underlying

Figure 8: IRR of black inks used for the Fisher Antiphonary. Inks depicted on fol. 1r showing black musical notation (a–c), black script (d–f) and black outlines of the illuminations (g–i). Micrographs recorded with the Dino-lite microscope under visible light (b, e, h) and nIR (940 nm) light (g, f, i).


layer. This effect is particularly enhanced due to the particulate nature of the brass paint. Apart from the different techniques used in the illumination of the Fisher Antiphonary, one of the most notable results is the change from gold to brass from folio 12v onwards. This can be explained by a change in the production process (different illuminators or lack of gold) or by the intentional use of real gold on the first few folios to make it look as if the manuscript was more valuable than in reality.

Figure 9: XRF results concerning the metallic decoration in the Fisher Antiphonary. The left-hand side shows an exemplary XRF spectrum of all areas made with gold leaf (a), such as buds (c), halos (e) and the background on the coat of arms (g). The right-hand side shows XRF spectra of different areas made with brass (b), such as brass leaf (d) and brass paint (f, h). All the spectra are normalized.


4 Case study II: Düsseldorf, Kunstpalast, Inv. K 1925-67Once we had finished our examination of the Fisher Antiphonary, art historian Ada Labriola kindly drew our attention to the Düsseldorf Fragment, which she identified as a copy of the bas-de-page miniature of Sq (fol. 121v, fig. 3), hence the same model for the bas-de-page miniature in the Fisher Antiphonary (fig. 1). By looking at the stylistics of the female organist (e.g. a personification of music) and her face, hands and clothing in particular, Labriola recognized modern features and dated the fragment to the 19th century. She considers the fragment to be part of the same folio from which a cutting was extracted that was formerly part of the Robert Lehman Collection (later kept in the Metropolitan Museum of Art, New York). This refers to the historiated initial “M” with the portrait of Francesco Landini, thus also a copy that refers to Sq, fol. 121v (fig. 3). Both items, the cutting and the Düsseldorf Fragment, are characterized by having a significantly higher quality of execution than the illuminations in the Fisher Antiphonary.

The cutting is reproduced (in black and white) in the Appendix of the catalogue for the 2003 exhibition “Treasures of a Lost Art: Italian Manuscript Painting of the Middle Ages and Renaissance”, organised by the Metropolitan Museum of Art and curated by Pia Palladino. In the catalogue, the cutting is described as a modern copy (Palladino 2003, p. 181), but although the cutting is part of the catalogue, it has not been put on display. The provenance of the cutting in unknown, but it was certainly part of the Lehman Collection in 1937 – at that time, it was dated to the 14th century (De Ricci & Wilson 1937, p. 1706, A.27). In 2004, the cutting was acquired by Dr. Jörn Günther Rare Books along with other miniatures, a firm then based in Hamburg (and now in Basel). In the same year, the cutting was sold to a private collector in Hamburg (email communication with Marion Hanke, Dr. Jörn Günther Rare Books, 20/11/2018). Since the current whereabouts of the cutting are unknown, we were unable to examine it any further.

The Düsseldorf Fragment is a parchment snippet that measures 93 × 283 mm. Its reverse side is blank except for an ownership stamp. It was purchased from Hans Rothschild’s Antiquarian Bookshop in Cologne on 3 April 1925 by the Städtisches Kunstmuseum Düsseldorf [Düsseldorf Civic Art Museum] for 1,050 Reichsmarks (see Düsseldorf, Kunstpalast, Zugangsverzeichnis der Graphischen Sammlung, 1913–26). By this time, it was assumed that the miniature was made by a 15th-century master from Siena, but the museum has now dated the creation of the fragment to somewhere around the end of the 18th century. Again, we were faced with extremely different attempts at dating. In the following, we will be able to verify Ada Labriola’s hypothesis by means of scientific methods.

As in case study I, the scientific results from X-ray fluorescence (XRF) and visible reflectance (VIS) measurements allow an assignment of the writing and painting materials used for the Düsseldorf Fragment. They are summarized in Table 2.

Table 2: Writing and painting materials identified in the Düsseldorf Fragment by XRF and VIS. Trace elements are given in brackets. a reflectance maximum, b inflection point (first derivative spectrum), c absorption features (Kubelka-Munk). References for the assignment of materials and their availability/first date of production as a pigment are given in the text.

Analysed areas XRF (elements) VIS (nm) Material assignment Availability

white Pb -- lead white since antiquity

orange Pb 570b red lead since antiquity

red Pb, Hg 590b vermillion since antiquity

red (stave lines) Hg 590b vermillion since antiquity

red (lower right part) Hg 590b vermillion since antiquity

pink Pb, Hg 600b vermillion since antiquity

yellow Pb, (Hg), (Zn) 520b, 570c, 640c organic dye? --

blue Pb, Co, (K), (Fe), (Ni), (As), (Bi) 450a, 500b smalt since 15th c.

green Pb, Cu, As 550a, 490b, 530b Scheele’s green 1778

gold Au, Ca, Sr, Fe -- gold leaf since antiquity

black (outlines) -- -- carbon ink since antiquity

black (script and musical notation) Fe, Zn, (Cu) -- iron-gall ink since antiquity


4.1 Scientific results

4.1.1 Colourants and gold

The XRF measurements mainly detected lead signals for the white and coloured areas of the miniature in the Düsseldorf Fragment (fig. 10). This shows that the pigment lead white (basic lead carbonate, 2PbCO3·Pb(OH)2) was used for all the white areas and for brightening the colour pigments.

The additional detection of mercury (Hg) for the red and pink areas of the illumination indicates vermillion (mercury sulphide, HgS). This was confirmed by our VIS measurements (fig. 11a), which display characteristic inflection points at 590 to 600 nm depending on the mixture with other pigments such as lead white (Oltrogge, 2008). Vermillion could also be detected for the red stave lines and the remnants of red in the lower right part of the fragment. Some text may have been deleted intentionally here. Only lead (Pb) signals could be detected for the orange decorations; these could have originated from lead white or from red lead, an orange pigment (lead oxide, Pb3O4). The determined inflection points at 570 nm (fig. 11a) confirm this result (Oltrogge, 2008). We cannot tell whether this pigment was used in a pure form or mixed with lead white, however.

As for the yellow areas, practically the only signals that could be detected in the XRF spectra were for Pb. This suggests the presence of a yellow lead oxide or an organic yellow dye. However, the reflection features determined by VIS (Table 2 and fig. 11c) cannot be assigned to any classical pigment or dye. Traces of zinc (Zn) indicate the use of a yellow lake, based on a yellow dye and zinc acting as a mordant. Traces of Hg can be caused by admixtures of cinnabar. Unfortunately, the analytical methods used could not provide any conclusive evidence in this case.

The XRF measurements of the blue areas (fig. 10) show characteristic signals for cobalt (Co) and traces for iron (Fe), nickel (Ni), arsenic (As) and bismuth (Bi). This signature can be clearly assigned to smalt, a blue cobalt glass pigment, which is contaminated by the aforementioned elements due to its production process (Spring, Higgitt & Saunders, 2005). VIS measurements (fig. 11b) again confirmed our XRF results, as they showed a reflectance spectrum characteristic of smalt with a maximum at 450 nm (Mühlethaler & Thissen, 1993). This pigment has been known in Europe ever since the Middle Ages and was widely used until the 19th century.

Focusing on the green areas, copper (Cu) and arsenic (As) could be detected there in addition to Pb. These elements can either originate from a pigment mixture of yellow orpiment (arsenic sulphide, As2S3) mixed with a blue colourant

Figure 10: XRF spectra of the white pigment and colourants (white, orange, red, pink, blue, yellow, green) used for the illumination in the Düsseldorf Fragment. The spectra are normalized to their highest signal in the low (left) and high (right) energy region.


or from a green copper arsenite. The results of the VIS measurements ruled out the former and thus confirmed the use of a green copper arsenite compound. These new pigments were only introduced in the 18th and 19th century. After the discovery of ‘Scheele’s green’ in 1775 and its patenting in 1778, however, it took several years until the paint manufacturer William Parker filed the first patent for this pigment (in 1812) and at the same time, another copper arsenite compound was discovered, which was widely produced as ‘Schweinfurt green’ or ‘emerald green’ from 1822 onwards (Fiedler & Bayard, 1997). Green copper arsenites can be present in numerous chemical modifications, but cannot be further distinguished by XRF analysis alone. Additional VIS measurements show a broad reflection maximum at 550 nm (fig. 11b), so this is more likely to be a copper orthoarsenite, a type of Scheele’s green (Scott, 2002). Therefore, it is possible to determine 1778 as a terminus post quem for the illumination of the Düsseldorf Fragment. Considering that Scheele’s green and all other copper arsenites were not widely used until after the turn of the century, it is unlikely the illumination work was performed before the beginning of the 19th century.

The use of gold leaf can be proved for the gilded areas of the Düsseldorf Fragment, as the XRF results (fig. 12a) we obtained show signals for gold (Au) along with iron (Fe), calcium (Ca) and strontium (Sr). The three latter elements may be due to the use of a preparatory layer composed of a basic calcium-containing layer and a coloured bole of iron oxides on which gold leaves were subsequently glued (Fuchs, 2018). The relatively high amount of Sr could suggest the use of gypsum (Franceschi & Locardi, 2014) as a ground layer. A further indication of the use of gold leaf is the coherent metallic surfaces and the visible striations resulting from polishing (fig. 12b).

4.1.2 Black inks

Further promising results were obtained by analysing the black inks used for the script and musical notation along with the black outlines of the illumination. Our XRF measurements initially showed a similar result to the one in the first case study. We detected iron (Fe), copper (Cu) and zinc (Zn) signals in script and musical notation, which clearly showed the presence of iron-gall ink. In contrast, the black outlines of the illumination did not exhibit any of these signals and thus can only originate from carbon-based inks. This was confirmed by infrared reflectography (IRR). The micrographs clearly show that iron-gall inks were used for the musical notation (fig. 13a, d) and script (fig. 13b, e) since they lose opacity at 940 nm (Rabin, Hahn & Binetti, 2014). In contrast, the black outlines of the illumination (fig. 13c, f) remained unchanged and can therefore be clearly assigned to carbon-based inks (Mrusek et al., 1995).

Besides this, the IRR images revealed preliminary drawings for the illumination (13f) and outlines for the script (13e) and musical notation (13d). Such pre-drawings for script or musical notation certainly do not exist in Medieval or Renaissance music manuscripts or choir books. In the Düsseldorf Fragment, the text and music were literally painted. This is not only a further indication that we are, indeed, dealing with a modern illumination, but it also makes the

Figure 11: Visible reflectance data collected from the coloured illuminations of the Düsseldorf Fragment. (a) Exemplary first derivative spectra of the orange, red and pink areas, (b) exemplary reflectance spectra of the blue, yellow and green areas, and (c) their exemplary first derivative curves. All the spectra are normalized.


practices of the copyist visible. Since the dimensions of the illumination, stave lines and musical notation are the same as in the original Sq manuscript, we assume that the pre-drawings were based on tracings made directly from Sq. We will return to the question of tracing in the following section.

Since the USB microscope only has a small field of view and its built-in illumination is limited to the near-infrared range (940 nm), we additionally examined the entire fragment with a state-of-the-art infrared camera to make all the pre-drawings visible (fig. 14b). Apart from the outlines in carbon ink that have been described, only the pre-drawing of the illumination, the script and musical notation are now clearly visible. Some areas, e.g. those of the blue and green colourants and the gold leaves, are also partially visible, as these absorb areas of infrared light similar to carbon-based inks and thus appear in different shades of grey in the image. All the other areas, especially the script performed in iron-gall ink, reflect the infrared light completely and are therefore no longer visible.

Figure 12: (a) Exemplary and normalized XRF spectrum of the gold decorations of the Düsseldorf Fragment, such as instruments and buds (b).

Figure 13: IRR of black inks used for the Düsseldorf Fragment for pre-drawings and outlines. Micrographs recorded with the Dino-lite microscope under visible light (a–c) and nIR (940 nm) light (d–f) showing musical notation (a, d), script (b, e) and illumination (c, f).


5 The illuminator’s palette and techniques in the second half of the 19th centuryIn both case studies we were able to show that certain colourants were used that were not developed and produced until the 18th or 19th century: For the later added illuminations of the Fisher Antiphonary (case study I) we could identify viridian (1859), zinc yellow (1847), zinc white (1834) and baryte (1793) and for the illuminations of the Düsseldorf Fragment (case study II) we could proof the use of a copper orthoarsenite, most likely Scheele’s green (1778), which however was only marketed as an artist pigment after the turn of the century. Certainly, the techniques used here are known from the examination of paintings and the respective painter’s or artist’s palette utilized in each case. In this study, however, we are especially interested in the Illuminator’s palette. The dates in parentheses represent each a reliable terminus post quem for the illumination of the examined manuscripts. Of particular interest is the use of viridian in the Fisher Antiphonary, which excludes illumination of that manuscript before the second half of the 19th century.

The second half of the 19th century saw renewed interest in illuminated manuscripts. Rowan Watson situates the beginnings of it in Great Britain in the late 1850’s (Watson 2007). He further describes how it became extremely popular among amateur painters and connects this to the availability of low-cost manuals, which described how to illuminate manuscripts. There was also a growing number of professional facsimilists at this point. Almost all of the manuals were published by companies – such as Winsor & Newton – that sold materials necessary for manuscript illumination, such as brushes, pigments and inks. Thus, the manuals mainly served advertising purposes.

The production of manuals is unquestionably a phenomenon that started in England; comparable publications were only found in France at the end of the 19th century. While 19th-century illumination is relatively well researched for Great Britain, this is not the case for Italy yet. Ada Labriola was able to show the beginnings of a new interest in manuscript illumination from about 1850, which was accompanied by the re-publication of Giorgio Vasari’s (1511–1574) “Lives of most excellent painters” and descriptions of Italian choir books and the illuminations contained therein. Medieval treatises on illumination such as Cennino Cennini’s (c.1370–1440) Libro dell’Arte were commented on and published (Labriola 2016). A volume comparable with the British manuals was only written by Vittorio Vulten in 1905, however (La Miniatura sulla pergamena. Corso teorico pratico). In addition to such manuals, template books were also provided that were similar to those in England, one example being A. Melani’s Manuale dell’Ornatista, which was published in Milan in 1896 by Hoepli. This work includes 24 colour plates which reproduce initials and border decorations from manuscripts and prints, among other things – miniaturists and calligraphers are explicitly named as their target groups.

The authors of the manuals not only give instructions on the art of illuminating, but also advise illuminators on choosing the most useful materials. In most cases, the manuals include advertisements in the form of catalogues produced by the respective companies, which included price lists as well. In the following, we will use this rich resource base to relate the information contained there to the measurement results from our case studies. Our focus of interest

Figure 14: This IRR image from the complete Düsseldorf Fragment was recorded with the 1510 Long Wave Pass filter.


is on the wide availability and use of the materials in the second half of the 19th century. The exact number of printed manuals is hard to estimate. We looked at 17 British manuals by 14 different authors, published between 1846 and 1906 and listed in Watson 2007 (fig. 15).

We noted the frequency of the authors’ recommendations (R) on pigments useful for manuscript illumination. Moreover, we were able to get additional information about their prices (given in pence) from the catalogues of firms and colourmen (paint dealers), which are enclosed in seven of these manuals. The selection gave us some initial insights into the matter (a comprehensive evaluation of all the manuals that have survived is still necessary, though). In order to ensure comparability and a broad temporal spread over the second half of the 19th century, we shall refer exclusively to English publications here.

There is no doubt that the colours and publications of the English companies were available throughout Europe. This can be seen in various advertising leaflets that promoted the products these companies were selling at the time, for instance. One example is an advertisement in the appendix of the Catalogo ufficiale illustrato (ed., R. Accademia di belle arti di Brera, 1891) by the Milan-based company of Luigi Calcaterra, who sold “Articoli per belle Arti”, i.e. paints, brushes and other artists’ accessories such as parchment for painting. The advertisement emphasizes that products are sold by renowned dealers in colourants and pigments from Düsseldorf, Nuremberg, Paris and London. The company of Winsor & Newton in London was mentioned explicitly.

5.1 Colours and gilding

Zinc white, mostly sold under the name of “Chinese White”, was recommended by most of the manuals’ authors (R = 12/17) and is described as a “material of the greatest use to the illuminator, combining with, and giving body to, all […] colours” (Audsley & Audsley, 1861, p. 31). In addition, this pigment is said to be “permanent, and the best adapted for Illuminating”, which “is not only useful per se, but is indispensable for toning or reducing other colours” (Ward, 1873, p. 13). These descriptions match up perfectly with the results obtained for case study I. “Chinese White” had been sold for one shilling (12 pence) since 1862, making it one of the most affordable pigments. Barytes (R = 8/12) were also available at a very low price at this time (just 18 pence) and were mainly used as fillers and for brightening coloured pigments. They were marketed as “Illuminating Body-White” for the art of illumination and were often promoted as being “undoubtedly the best” and “the most permanent white yet manufactured” (Harrison, 1863, p. 31). In contrast, lead white is only mentioned once – in a very early manual where the entry is said to be “liable to change” (O’Neill, 1846, p. 51). It does not appear at all in the later manuals, though, as by then it was known to cause lead poisoning; consequently, it was mainly replaced by zinc white from the middle of the 19th century onwards. Nevertheless, lead white continued to be available in paint manufacturers’ catalogues, usually sold cheaply for only a shilling (12 pence) under the name of “Flake White”. Its identification in case study II is not surprising in view of its availability. It should also be noted that zinc white initially found little acceptance among artists due to its lower permanence compared to lead white, and its large-scale industrial production only began in 1845 (in Paris) – and even later in other European countries (Kühn 1986).

At the same time, paint dealers also started to offer new chromate pigments, viz. zinc yellow and viridian, which were mainly sold under the names of “Lemon Yellow” and “Green Oxide of Chromium” respectively. These are first mentioned in the manuals of the 1860s and were already available at a moderate price from George Rowney in 1861; neither of the colours were listed by Winsor & Newton yet, however. Lemon yellow was sold for only two shillings (24 pence) and was often recommended (R = 7/17), e.g. as “a vivid pale yellow, of great use to the illuminator” (Audsley & Audsley, 1861, p. 31). In Rowney’s catalogues, the price of “Green Oxide of Chromium” dropped from three shillings to two in 1862 and was then increasingly advertised in later manuals (R = 8/17). It is described as a “useful, rich, deep-toned opaque green” for illuminating manuscripts (Audsley & Audsley, 1861, p. 29). In a later manual, it is recommended as “a very good permanent green[,which] is rather a thin colour, and requires body, which may be given with lemon yellow, or with white and yellow ochre; being a rather bluish green, it is the better for a little yellow” (Johnston, 1906, p. 178). This corresponds to the XRF results obtained for the green colourant of the Fisher Antiphonary (case study I) since the relatively high barium (Ba) and iron (Fe) signals (fig. 5a) can be explained by the admixture of baryte as a white filler and yellow ochre (iron-oxide pigment) as a final tinting element. The green pigment most frequently mentioned in the manuals is “Emerald Green” (R = 15/17), which was discovered in the course of improving Scheele’s green at the


beginning of the 19th century. However, both copper arsenites – which are slightly different in their chemical composition – were generally called emerald green and were marketed accordingly (the catalogues in the manuals only list emerald green, in fact). Although the results from case study II provide evidence of Scheele’s green being used, it would be not surprising if the illuminator actually obtained a paint with a different composition from the retailer.

The red and orange pigments identified in this study also agree to a large extent with the recommendations in the manuals we examined. Madder-based pigments were sold as “Madder Lake” or “Rose Madder” for three shillings (36 pence) and were recommended by most of the authors (R = 13/17). They are described as being the “most beautiful and permanent reds[, which are] of the greatest value to the illuminator” (Cooper, 1868, p. 15). However, in order to obtain pink and purple mixtures, artists were instructed to use insect-based pigments: “Carmine” (R = 8/12) and “Crimson Lake” (R = 7/12). In his Hints on Illuminating, Lucien reports:

“Most pink reds are obtained with carmine or lake, paled with Illuminating Body White, or diluted with water. With French ultramarine and carmine we get a rich warm purple. Crimson Lake may be sometimes substituted for carmine. It has a bluer tint, and is, erroneously, as we believe, said to be more permanent” (Lucien, 1870, p. 27).

Figure 15: Chart showing the pigments identified in both case studies (left) and the information extracted from the 17 manuals investigated (bottom; only the first author is mentioned) and enclosed catalogues (top). The circles indicate recommendations (R) by the manual’s authors, which are summarized as a ratio on the right. The numbers inside the circles show the prices of these pigments given for cakes of watercolours in pence and coloured from low to high in blue, green, yellow, orange and red.


These descriptions tally with the results obtained in case study I. Given the large price difference, we assume that the artist of the Fisher Antiphonary used a crimson lake (18 pence) rather than expensive carmine (60 pence). The authors’ comments on the use of red lead also agree with the results obtained in our study. Although this classic orange to red pigment is rarely mentioned in the manuals (R = 4/17) and the reader is often warned about its poor permanence, the illuminating artist William James Audsley describes red lead as “a useful colour when it can be carefully protected” (Audsley & Audsley, 1861, p. 28). This can be done by applying a further layer of transparent colour, such as madder lake, and is described in detail by Lucien. He recommends the use of a fixative, which “fixes the colour so that it may be washed over freely, […] increases the depth and brilliancy of the colours[ and] is also useful for casing fugitive colours” (Lucien, 1870, p. 25). As we said previously, our methods are unable to detect an organic fixative, but Lucien’s instructions correspond with the application of madder lake over red lead for the red areas in case study I. In contrast, the red areas of the Düsseldorf Fragment are painted with cinnabar, which, like red lead, was available at low cost for just a shilling (12 pence). Most of the authors (R = 15/17) claim it “will retain its brightness for any length of time, as will be seen on an examination of some of the oldest manuscripts” (Jewitt, 1860, p. 38). Other manuals also recommend mixing vermilion with lead white to obtain a pink hue, “which is called Rosa” (Shaw, 1866, p. 62; Wyatt & Tymms, 1860–1866, p. 76) and perfectly matches the results obtained in case study II.

As for blue paint, artificial ultramarine was frequently recommended (R = 16/17). Upon its appearance in the 1830s, firms and colourmen began to offer a more affordable substitute for lapis lazuli, which was a rare mineral. It was sold under the names of “French Blue”, “French Ultra” or “French Ultramarine” for two to three shillings, about a tenth of the price of natural ultramarine. Audsley mentions the prominent role of this “very useful colour, which ably takes the place of real ultramarine; and combined with white – white and carmine – and white and cobalt, […] forms a valuable set of beautiful colours in blues and lilacs. It is permanent; and if good, strong and brilliant” (Audsley & Audsley, 1861, p. 27). Again, this is very much in line with the findings we made in case study I. In contrast, the use of smalt in case study II is surprising because this pigment was quite expensive (60 pence) compared to artificial ultramarine and it was also recommended less frequently (R = 6/17). However, O’Neill describes it as “a bright deep blue, permanent, considerably power, washes badly; is used principally for flowers and draperies” (O’Neill, 1846, p. 40).

In addition to colour recommendations, the manuals also provide detailed instructions on gilding manuscripts. A comprehensive description of the various techniques and materials is provided in Wyatt & Tymms’ manual, which, like the others, recommends the use of gold leaf as “by far the best and most useful metallic preparation[, but] the difficulty of handling and laying it on deters amateurs from employing it” (Wyatt & Tymms, 1860–1866, p. 86). They also say that most paint manufacturers offer special mixtures for the application of gold leaf, such as “gold size [and] raising preparation[, which] is adapted for raising the surface of the work, so as to obtain relief, and is particularly required for imitating rich MSS. of the 14th and 15th centuries” (Wyatt & Tymms, 1860–1866, p. 88). Although “the amateur may, of course, prepare mordants of different degrees of tenacity and body for his own use, his time will be more profitably spent in improving himself in design than it could be (nowadays) in experimenting on the ‘materia technica’ of art” (Wyatt & Tymms, 1860–1866, pp. 88–89). Renowned illuminating artists worked closely with paint manufacturers and thus specifically recommended their products, such as “Audsley’s Mediaeval Raising Preparation” (Audsley & Audsley, 1861, p. 38) sold by George Rowney and Co. or a special preparation that William Randle Harrison developed in the 1860s named “Medieval Gold-Body”, which could be used “to meet all the requirements of the modern illuminator” (Harrison, 1863, p. 32). The detection of calcium and iron in the XRF measurements of the gilded areas in both case studies (fig. 9a and fig. 12a) suggests the use of such a preparation. The intentional change from gold to brass in the Fisher Antiphonary was probably for economic reasons. While most manuals “warn [their] readers against the use of any inferior, or imitation preparation […] such as Bronzes, Inks, and Paints, none of which will bear exposure untarnished” (Audsley & Audsley, 1861, p. 33), the illuminating artist Marcus Ward says if “there is a considerable expanse of gold surface required, it becomes necessary to use a substitute for the precious metal. For this purpose, fine gold bronze powder is generally employed, mixed up with gum-water, and used as paint. On drying, it possesses all the appearance of real gold, at only a fraction of the expense. If too much gum is used in mixing, much of the metallic lustre will be lost; while, if too little, the bronze powder will rub off” (Ward, 1873, p. 16).


5.2 Colour boxes

The close cooperation between the authors of the manuals, some of whom were illuminating artists themselves, and the paint manufacturers is also evident in the marketing of colour boxes, which were specially made for the purpose of manuscript illumination (fig. 16). Wyatt & Tymms mention that “Messrs. Winsor & Newton, Rowney, Barnard, Newman, and others, fit up boxes with special selections of all requisite materials; including all that can be wanted for the application and burnishing of gold and other metals” (Wyatt & Tymms, 1860–1866, p. 81).

David Laurent de Lara, the founder of the Illuminating Art Society (Watson, 2007), even marketed his own “Chromographic colour-box, for the use of illuminators[, which could] be obtained from the author or at any of the author’s agents” (Laurent de Lara, 1856, p. 18). In his later manual from 1863, there are advertisements by the paint manufacturers Ackerman & Co. and James Newman as well as a catalogue by Reeves & Sons with colour boxes in various sizes (fig. 16a). In the same year, he also “warn[s] the purchaser not to be allured by the sounding title of an ‘Illuminating Colour-box’, though highly-priced and costly fitted up, but to purchase that only which is likely and capable of answering his purpose” (Laurent de Lara, 1863, p. 33). He was alluding to the offers of other competing manufacturers who also marketed similar paint boxes, such as J. Barnard (fig. 16b), George Rowney (fig. 16c) and Winsor & Newton (fig. 16d). Rowney points out how flexible his colour boxes are in his catalogues, saying: “[b]oxes may be obtained, fitted to any arrangement required” (Laurent de Lara, 1863, p. 141). Whether the illuminators of the Fisher Antiphonary and the Düsseldorf Fragment actually used such colour boxes cannot be confirmed conclusively, however. Despite their recommendations and marketing in the 1860s, Shaw, for example, advises “that a costly colour-box is by no means required for that purpose. The finest productions, especially of the early schools, were as remarkable for their simplicity, and for the few pigments employed on them, as for the care with which the artists selected the most brilliant and the most permanent” (Shaw, 1866, p. 61).

Figure 16: Four examples of the colour boxes shown in 19th-century manuals: a) Laurent de Lara, 1863; b) Jewitt, 1860, p. 1; c) Audsley & Audsley, 1861; d) Bradley, 1861.


5.3 Tracing

In addition to providing recommendations on suitable illuminating materials, the manuals also include detailed descriptions on how to make exact copies by tracing. The procedure is described by all the authors in a similar way and matches up with the IRR results we obtained in case study II. First of all, they say a thin piece of transparent tracing paper is placed over the manuscript that is to be copied so that the outlines can be traced with a fine pencil. The tracing paper is then placed over the material to be illuminated (paper, cardboard or parchment/vellum). To transfer the tracing, a piece of transfer paper is needed in between, which is powdered with black lead or red chalk on the lower side. When traversing the outlines with a tracing point, the powder particles on the transfer paper are transferred to the support material. The transferred outlines can then be redrawn in ink and finally painted and decorated in colour to obtain an exact copy. Wyatt & Tymms say that by “adopting this method of working, with care and neatness of hand, very agreeable results may be obtained, without it being indispensable for the illuminator to be a skilful draughtsman”, and they further remark that “if cleverly managed, it will be impossible to detect that that [tracing] material has ever been employed” (Wyatt & Tymms, 1860–1866, p. 53). State-of-the-art technologies such as infrared reflectography, however, are capable of revealing such tracings if transfer paper powdered with black lead (graphite) was used. Graphite is a crystalline form of carbon and thus remains visible in infrared light (Mrusek et al., 1995), as we can clearly see for all the pre-drawings and outlines of the Düsseldorf Fragment (fig. 14). The infrared images also show that the exemplar was not traced completely, as some details were omitted. This result tallies with the instructions given by the authors of the manuals. Lucien mentions that “[i]n tracing, only the necessary or guiding lines should be drawn on the transparent tracing paper, otherwise much confusion ensues [sic]; besides, no end is achieved by marking the position of lines which can be put in with a brush and colour at once by the eye – but rather harm, as often a black mark is transferred which is found afterwards to mar the effect of the finished painting” (Lucien, 1870, p. 22). Others remark that “[s]mall parts such as heads, &c., should not have all the minutiae traced, but should be sketched apart larger on your tracing” (Bradley, 1861, p. 83). More detailed instructions are given by Laurent de Lara, who writes: “Above all things, be correct; do not trace more than is necessary for your object, and avoid details, which may more easily be put in by the eye. Too much tracing often confuses [the tracer]. The upper and inner line of the hair, the eyebrows, the line of the nose, the upper line of each eyelid, the central line of the mouth, and the contour of the cheek and chin [are] sufficient to give a correct tracing of a face; if you trace more, in retracing it you will get confused” (Laurent de Lara, 1856, p. 38). These remarks coincide to a large extent with the results of case study II, in which we only observed traced guidelines for illuminations, script and musical notation (fig. 13). At the same time, adaptions were made, probably on the tracing paper before the tracing was transferred, and especially concerning the organist’s face – changes that corresponded to 19th-century taste, as Labriola just observed.

6 Conclusions and outlookIn our study, we were able to narrow down the period of time when the Fisher Antiphonary and the Düsseldorf Fragment were illuminated: scientific analysis proved that the manuscripts were not illuminated before the 19th century and that the Fisher Antiphonary was not illuminated before the second half of that century. The illuminations in the Fisher Antiphonary were not added after 1908 either, and those in the Düsseldorf Fragment were not done after 1925. Valuable information from a variety of manuals on illumination from the period in question allowed us to further contextualise the two manuscripts under investigation in terms of illumination practices in use in the second half of the 19th century. On the basis of our results, it will now be possible to situate the two manuscripts in a larger context involving further manuscripts whose illuminations were likewise copied from the Squarcialupi Codex. Further publications on this neglected topic will be published in the near future.

Acknowledgments: We would like to thank the following institutions and people who have supported our work in a remarkable way and without whom we would not have been able to conduct this study. In Toronto, we were warmly welcomed by the Thomas Fisher Rare Book Library and its staff and received great support from them during our stay. We would especially like to thank Pierce J. Carefoot, who was open to the project from the very beginning and provided


the premises in which we were able to conduct our measurements. Loryl MacDonald generously supported us with extra time when it became short. Kathleen Wilson Ruffo kindly granted us access to the archives of the Royal Ontario Museum and its card catalogue. Dmitry Gavrilov (then at the University of Windsor) supported us with the necessary licence for Canada to use XRF instruments on site. He was also a perfect guide and we thank him for introducing us to his colleague A. Keith.

We also received whatever we needed for our work in Düsseldorf. We would especially like to thank Sonja Brink and Claudia Petersen from the Department of Prints and Drawings at the Kunstpalast. We learnt of the existence of the fragment deposited there and examined in case study II from Ada Labriola (Florence), whom we thank for that and for her comments on this paper. We also thank Oliver Hahn (Berlin/Hamburg) for his valuable feedback. Further important support was kindly provided by Roman G. Maev (Windsor) and Ira Rabin (Berlin/Hamburg).

Funding Information: This research was funded by the German Research Foundation (Deutsche Forschungs-gemeinschaft, DFG), first as part of Sonderforschungsbereich 950 (SFB 950, a collaborative research centre) and then under Germany’s Excellence Strategy programme (EXC 2176 “Understanding Written Artefacts: Material, Interaction and Transmission in Manuscript Cultures”, project no. 390893796). The research was conducted within the scope of the work conducted at the Centre for the Study of Manuscript Cultures (CSMC) at Hamburg University.

Author Contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

Conflict of Interest: Authors state no conflict of interest.

Data Availability Statement: The datasets generated during and/or analysed during the current study are available in the ZFDM Repository, Universität Hamburg:

– http://doi.org/10.25592/uhhfdm.1419 – http://doi.org/10.25592/uhhfdm.1421

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