History of Pigments

This review summarises the state-of-the-art of lead-based pigment studies, addressing their production, trade, use and possible alteration. Other issues, such as those related to the investigation and protection of artworks bearing lead-based pigments are also presented. The focus is mineralogical, as both raw materials and degradation products are mineral phases occurring in nature (except for very few cases). The minerals described are abellaite, anglesite, blixite, caledonite, challacolloite, cerussite, cotunnite, crocoite, galena, grootfonteinite, hydrocerussite, laurionite, leadhillite, litharge, macphersonite, massicot, mimetite, minium, palmierite, phosgenite, plattnerite, plumbonacrite, schulténite, scrutinyite, somersetite, susannite, vanadinite and an unnamed phase (PbMg(CO3)2). The pigments discussed are lead white, red lead, litharge, massicot, lead-tin yellow, lead-tin-antimony yellow, lead-chromate yellow and Naples yellow. An attempt is made to describe the history, technology and alteration of these pigments in the most complete manner possible, despite the topic's evident breadth. Finally, an insight into the analytical methods that can (and should) be used for accurate archaeometric investigations and a summary of key concepts conclude this review, along with a further list of references for use as a starting point for further research.

This article summarises the history of cinnabar, from its first uses in burials to modern oils on canvas. After a brief introduction on mercury and contamination issues, the article gets to the heart of the topic. First, mercury-based minerals significant for studying pigments, i.e. cinnabar, metacinnabar, hypercinnabar and calomel, are presented. Structural information and properties precede an overview of the geographic distribution of cinnabar deposits. The following section addresses the multiple uses of cinnabar, divided into funerary use, decorative use, lustre and Chinese lacquer production. The use of cinnabar for writing (ink), medicine and cosmetics is briefly described, and a shortlist of uncommon finds is further provided. The following section approaches inherent but less known topics such as cinnabar procurement, trade, production technology, application and alteration. An entire section is dedicated to calomel before concluding with an overview of the analytical methods for the characterisation and provenance investigation of cinnabar. Keywords Cinnabar-metacinnabar-hypercinnabar. Vermilion and pigment analysis. White mercury and calomel, corderoite and terlinguaite. Archaeometry and archaeology well as an overview of glass-based pigments (Cavallo and Riccardi 2021) are also presented. Furthermore, two papers on cosmetic (Pérez-Arantegui 2021) and bioactive (antibacterial) pigments (Knapp et al. 2021) provide insights into the variety and different uses of these materials.

This review offers an update on arsenic-bearing minerals and pigments with the aim of serving as a guide for the study of Cultural Heritage materials in which these materials can be found. The different As-bearing mineral phases (realgar, pararealgar, orpiment, anorpiment, alacranite, dimorphite, bonazziite, uzonite, wakabayashilite, duranusite, arsenolite and claudetite) and some of their light-induced products are examined. The occurrence of As-sulfides and their trade, use, alteration and degradation are also reviewed. Finally, the analytical techniques commonly used for the identification of arsenic-containing pigments are discussed. The manuscript concludes with a good practice guide and a summary of key concepts for use by those working in the field of cultural heritage.
This article is part of the Topical Collection on Mortars, plasters and pigments: Research questions and answers

Within the Topical Collection, this paper represents an introductory contribution aimed at describing and discussing the research questions and the sampling criteria in the field of mortars, plasters and pigments studies. The paper is divided into three parts. In the first part, some terminological issues are clarified and the building archaeology is introduced as an indispensable method for sampling and interpreting archaeometric results. In the second part, the most common research questions are presented and discussed. Some case studies are also reported to clarify what the expected results may be. The sampling problem is faced in the third part, where the criteria for a representative, functional and suitable selection are provided.

The use of manganese and iron oxides by late Neandertals is well documented in Europe, especially for the period 60–40 kya. Such finds often have been interpreted as pigments even though their exact function is largely unknown. Here we report significantly older iron oxide finds that constitute the earliest documented use of red ochre by Neandertals. These finds were small concentrates of red material retrieved during excavations at Maastricht-Belvédère, The Netherlands. The excavations exposed a series of well-preserved flint artifact (and occasionally bone) scatters, formed in a river valley setting during a late Middle Pleistocene full interglacial period. Samples of the reddish material were submitted to various forms of analyses to study their physical properties. All analyses identified the red material as hematite. This is a nonlocal material that was imported to the site, possibly over dozens of kilometers. Identification of the Maastricht-Belvédère finds as hematite pushes the use of red ochre by (early) Neandertals back in time significantly, to minimally 200–250 kya (i.e., to the same time range as the early ochre use in the African record).

This article surveys pigment terminology attested in ancient Egypt, Mesopotamia, Greece, and the Roman Empire. Various sources survive, ranging from artists who detailed the materials they used in daily life, lists of medical ingredients, to encyclopedic texts that sought to explore the available corpus of known pigments. While the etymology is not understood for all early pigments, one trend in the Near East was that pigment names could be borrowed from more prestigious natural materials, such as lapis lazuli or gold. In the Greek and Roman worlds, a greater variety of pigments were available especially due to the broader geographic expanse from which to mine or produce pigments. A few trends persist in Greco-Roman pigment nomenclature. Some pigments continue to be named after natural materials. Other pigments are named after factors such as their provenance, color, an innovator, or their process of manufacture.

Many Andean textiles are painted, a tradition practiced across the Andes as early as the Lithic period (ca. 10000-4000 B.C.E). Despite its prevalence and aesthetics, research into painted textile technology is limited. Recently, samples from nine painted Andean textiles were collected from different museums and analyzed at the Getty Conservation Institute in Los Angeles. The samples represent a range of cultures, locations, and times. Analytical techniques included polarized light microscopy and X-ray florescence spectroscopy. Due to the paucity of published data on painted textiles, a comparison is made with mural paintings. Results show that Andean painters used a range of pigments, including ocher and cinnabar, and that pigments were chosen based on their chemical and physical characteristics from at least the Early Horizon period (ca. 950 B.C.E.-200 C.E.) onward, although there were also cultural preferences for specific pigments. The quality of the cinnabar pigment especially shows that Andean painters had great technical knowledge and skills, superior to what was previously suspected. Patterns of pigment choice and application indicate that painted textiles were primarily produced for funerary purposes.

The ceramics and pigments of Late Bronze Age (LBA) painted Canaanite pottery were studied using ceramic petrography and three microbeam methods: pXRF, LA-ICP-MS and EPMA. The analyses focused on specimens from Tel Esur in Israel’s northeastern Sharon Plain, which has yielded a well-preserved assemblage of the 15th/14th centuries BCE. We studied painted jars, biconical jugs and a bowl decorated with black, red or two-colored geometric patterns. The petrographic analysis revealed that the majority of the painted vessels were produced on the southern Levantine coastal plain. The microbeam analyses demonstrated the use of ferromanganese and ferric-iron pigments for the black and the red decorations respectively. The adoption of the manganese-based technique in Canaanite workshops seems to be an early LBA technological progress, which facilitated the production of black decoration while firing vessels in an oxidizing atmosphere; it explains the sharp increase in the production of two-colored Canaanite pottery during that period. Ferromanganese ore sources for the black pigment are rare in Canaan and absent from its coast; this required importation of raw ore from external sources. The analogous use of the manganese-based technique for black decoration on Cypriot wares suggests that both pigments and technology were transferred from Cyprus to Canaan, highlighting a ‘new’ aspect in the multifaceted Cypro-Canaanite liaisons of this period.

The use of red iron-based earth pigments, or ochre, is a key component of early symbolic behaviours for anatomically modern humans and possibly Neanderthals. We present the first ochre provenance study in Central Europe showing long-term selection strategies by inhabitants of cave sites in southwestern Germany during the Upper Palaeolithic (43-14.5ka). Ochre artefacts from Hohle Fels, Geißenklösterle and Vogelherd, and local and extra-local sources, were investigated using neutron activation analysis (NAA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that local ochre sources were continuously and systematically accessed for c.29500years, with periodic events of long-distance (about > 300km) ochre acquisition during the Aurignacian (c.35-43ka), suggesting higher mobility than previously suspected. The results reveal previously unknown long-term, complex spatio-temporal behavioural patterns during the earliest presence of Homo sapiens in Europe.

Velliky, E. C.& B. L. MacDonald & M. Porr & N. J. Conard 2020. First large-scale provenance study of pigments reveals new complex behavioural patterns during the Upper Palaeolithic of south-western Germany. Archaeometry, doi:10.1111/arcm.12611.

Mineral compounds, as pigments and therapeutics, appeared regularly in the technical and medical texts of the Greco-Roman (G-R) world. We have referred to them as 'G-R medicinal minerals' and we suggest that despite their seeming familiarity, there are actually many unknowns regarding their precise nature and/or purported pharmacological attributes. Earth pigments are part of that group. This paper presents a brief overview of our work over the past twenty years relating to: a. the attempt to locate a select number of them in the places of their origin; b. their chemical/mineralogical characterization; c. the study of their ecology via the identification of the microorganisms surrounding them; d. their testing as antibacterials against known pathogens. In the process, and to fulfil the above, we have developed a novel methodological approach which includes a range of analytical techniques used across many disciplines (mineralogy, geochemistry, DNA extraction and microbiology). This paper focuses on a select number of earth pigments deriving from the island of Melos in the SW Aegean, celebrated in antiquity for its Melian Earth, a white pigment, and asks whether they might display antibacterial activity. We demonstrate that some (but not all) yellow, green and black earth pigments do. We also show that the manner in which they were dispensed (as powders or leachates) was equally important. The results, although preliminary, are informative. Given their use since deep time, earth pigments have never lost their relevance. We suggest that the study of their ecology/mineralogy and potential bioactivity allows for a better understanding of how our perception of them, as both pigments and therapeutics, may have evolved.

The results of the first elemental and structural physicochemical analyses (SEM–EDX, TXRF, XRD, FTIR, GC and EDXRF) of Early Neolithic red pigment samples from the region of Valencia confirm one of the earliest uses of cinnabar (HgS) in Spain (5300 to 5000 cal bc). They also inform on the storage of massive quantities of hematite and the development of specific technologies of hematite-based paint production and use. The samples were recovered at the three most significant Early Neolithic sites of the Mediterranean coast of Spain: Cova de l'Or (Beniarrés, Alacant), Cova de la Sarsa (Bocairent, Valencia) and Cova Fosca (Vall d'Ebo, Valencia), which together have provided the most important European collection of Cardial ceramic ware (chronoculturally diagnostic of the Early Neolithic).

The use of red pigments linked to burial practices is widely documented in the Iberian prehistoric record and very often it has been traditionally interpreted as a ritual practice entailing the utilisation of local raw materials (iron oxides). Some research works, nevertheless, have also detected the use of red pigments which can only be interpreted as allochthonous. The red pigments spread over a single inhumation in a monumental Megalithic tomb surrounding Valencina de la Concepción Copper Age settlement was studied by means of X-ray diffraction, field emission scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray microfluorescence, micro-Raman and Fourier transform infrared spectroscopies. This approach allowed characterising the red pigments as cinnabar, mixed with tiny amounts of iron oxides. The presence of cinnabar, a product that was necessarily imported, in a context of an exceptional set of grave goods, suggests that the use of cinnabar was linked not only to ritual but also to practices related to the display of social status.

Pigments from paint palettes and a grindstone excavated from the pharaonic town of
AmaraWest (c. 1300–1050 BCE), which lies between the Second and Third Cataracts of the Nile, were
examined using polarized light microscopy, attenuated total reflection Fourier transform infrared
spectroscopy (ATR-FTIR), X-ray diffraction, and scanning electron microscopy with energy dispersive
X-ray spectroscopy. Most of the pigments were consistent with the typical ancient Egyptian palette,
but the greens and some blues were unusual. Two types of green pigment were identified, chlorite
(varieties clinochlore and penninite) and copper chloride hydroxide (atacamite type). The former
constitutes a type of green earth which has only rarely been identified in pharaonic Egyptian contexts
and may be more widespread than is currently reported. The majority of the blue pigment samples
were Egyptian blue, but some were found to be a blue earth, the main component of which being
sodic amphibole riebeckite. The use of this mineral as a pigment has not previously been reported in
any Nile Valley context. These results prompt questions around local and potentially indigenous
practices within an ancient colonial context, and highlight avenues for future research.

This special issue, “Looking ahead: new approaches to medieval Iberian heritage”, is the main output of a fruitful collaboration between the humanities and the experimental sciences, which has greatly contributed to increase our knowledge of creative processes in medieval Iberia. The articles examine a wide range of objects produced using very different media, such as illuminated manuscripts, glass, monumental painted altarpieces and azulejos (glazed tiles). Some of these objects were studied for the first time in the framework of this project, while others had received very little attention previously. Moreover, several of the case studies concern unfinished works, which gives us an opportunity to better approach the creative processes. This introductory article aims to establish the main overarching themes that have emerged from the joint efforts of the participating scholars and teams. These themes include the multicultural context of medieval Iberia, a revision of the traditional notion of the medieval workshop, a consideration of the materials used to construct colours and molecular palettes, and the transfer of technological processes between the different cultural and religious horizons that coexisted in the Iberian Peninsula. This paper also investigates the new avenues of research that the articles have opened, such as the role played by medieval Iberia in a broader European, Mediterranean and global context regarding the arrival of precious materials from the Far East.

The adult striped pattern of zebrafish is composed of melanophores, iridophores and xanthophores arranged in superimposed layers in the skin. Previous studies have revealed that the assembly of pigment cells into stripes involves heterotypic interactions between all three chromatophore types. Here we investigate the role of homotypic interactions between cells of the same chromatophore type. Introduction of labelled progenitors into mutants lacking the corresponding cell type allowed us to define the impact of competitive interactions via long-term in vivo imaging. In the absence of endogenous cells, transplanted iridophores and xanthophores show an increased rate of proliferation and spread as a coherent net into vacant space. By contrast, melanophores have a limited capacity to spread in the skin even in the absence of competing endogenous cells. Our study reveals a key role for homotypic competitive interactions in determining number, direction of migration and individual spacing of cells within chromatophore populations.

Archaeological research has identified the use of cultivated cotton (Gossypium barbadense) in the ancient Andes dating back to at least 7800 years ago. Because of unusual circumstances of preservation, 6000-year-old cotton fabrics from the Preceramic site of Huaca Prieta on the north coast of Peru retained traces of a blue pigment that was analyzed and positively identified as an indigoid dye (indigotin), making it the earliest known use of indigo in the world, derived most likely from Indigofera spp. native to South America. This predates by ~1500 years
the earliest reported use of indigo in the Old World, from Fifth Dynasty Egypt [ca. 4400 BP (before present)]. Indigo is one of the most valued and most globally widespread dyes of antiquity and of the present era (it being the blue of blue jeans).

An analytical study of First Nations painted objects from the Northwest Coast showed that green earth (celadonite) was used as a green pigment by Tlingit, Haida and Tsimshian artists. Green earth appears to have been used less frequently by Heiltsuk and Kwakwaka’wakw artists and was not found on Coast Salish or Nuu-chah-nulth objects. Microscopical samples of green paint from 82 Northwest Coast objects, as well as several pigment sources and mineral specimens, were analysed using Fourier transform infrared spectroscopy or X-ray diffraction. Green earth was the most frequently identified green pigment, found in approximately 40% of the samples.

Consultable:
https://rdcu.be/b45eb


Since prehistoric times, iron ore has been traded to be used for various purposes as in medicines, pigments, and cosmetics. This non-metallurgical iron ore trade, involving the transportation of ore from the mined deposits via trade hubs to consumption areas, must be viewed as part of a long-distance trading network, such as that for the trading of iron bars. This paper proposes an initial synthesis of (i) the circulation of iron ore fragments in the western Mediterranean and (ii) their multiple non-metallurgical uses in antiquity, as recorded in Naturalis Historia by Pliny the Elder. The basis of our discussion is a heterogeneous, concatenated chemical database, set up to assess the sourcing of iron ore fragments discovered in the Roman harbor of Colonia Narbo Martius (Narbonne, Aude, France). Lastly, we advance that in antiquity, iron ore was traded from Elba and possibly from southern Tuscany to Gaul, via the harbor of Colonia Narbo Martius, probably for use in medicine and as a coloring base. However, further development of this topic is required, since this trade is part of a larger, more complex network of distribution.

A Merovingian crucible fragment, with internally adhering yellow glass, and yellow glass beads of the same region and period were investigated by non-destructive XRF, optical microscopy and SEM-EDS. Although the microstructure and chemical composition of the yellow pigment (lead–tin yellow type II, ‘PbSnO3’) are almost identical in both the beads and the crucible, in the latter the pigment occurs in a much higher concentration. However, the glass base in the beads and the crucible is very different, indicating that the beads were not manufactured directly from the crucible. Instead, the crucible most likely served to produce lead–tin yellow, which was subsequently mixed elsewhere with a colourless soda–lime glass to produce yellow glass beads.

In September 2013 pigment samples were taken by one of the authors from pictograms inside the Goda
Roriso rock-shelter.1 The samples originated from white beeswax, previously analysed by micro-Raman
Spectroscopy. In addition to the samples, a series of chronometric dates were made from the same
substance. The radiocarbon dates were produced using Accelerator Mass Spectrometry (AMS).
Stylistically, the pictograms from Goda Roriso originate from an Ethiopian pastoral rock-art tradition
that is associated with a Neolithic agro-pastoral economy, chronologically attributed by the scholars to
4000 until 1300 BP. Our initial thought was that, based on style, the pictograms, in particular the images
of humped bovines, fell into a date range of between 2000 and 2500 years BP. The results revealed an
unexpected range of dates: AD1021e1060 and AD1062e1155 (for sample Beta358358) and AD894e928
and AD934e1017 (for sample Beta358359). Absolute dating demonstrated that beeswax application was
not a recent event, but doesn't belong to Neolithic Period. Based on secure chronometric dating, the
beeswax paintings of Goda Roriso are the oldest of their type outside Australia.
In this brief paper, we argue that beeswax forms an important by-product of beekeeping and that its
dates from this remote corner of Africa are synchronous with beeswax paintings found elsewhere, in
particular, within pre- and post-colonial Australia.

The current interdisciplinary study of a funerary portrait has provided the first identification of a blue pigment on Palmyrene sculpture. The exceptional attestation of lapis lazuli on the examined portrait confirms the use of this highly valuable semiprecious stone in ancient polychromy, which was previously thought to be a later addition to the painter’s palette. Considering that the archaeological record contains numerous minor objects carved from lapis lazuli, there are astonishingly few known instances of its use as a pigment. This Palmyrene discovery is only the third known example from Antiquity

The miniatures of the Pentateuch have been analysed in non-invasive way by means of UV-visible diffuse reflectance spectrophotometry with optical fibres (FORS), spectrofluorimetry and X-ray fluorescence spectro-metry (XRF) in order to characterise its palette and to compare it with those of other early medieval manuscripts. The results of this investigation highlighted the wide use of the pigment Egyptian blue, an unusual feature in miniature painting; moreover this synthetic pigment appears to have been produced following a non-traditional manufacture, due to the analytical evidence of a copper/zinc alloy as source of copper instead of the traditional sources used by Egyptians and Romans, i.e. copper, copper minerals or bronze.

This research has been centred on the analytical identification of the use of cinnabar (the red mercury sulphide-HgS-) as a pigment in Neolithic and Chalcolithic archaeological contexts (VI to III millennia B.C.) and in the determination of its possible origin by the application of Lead Isotopes analysis. In order to confront the isotopic results of the archaeological cinnabar pigments, samples from the mercury sulphide mineral deposits of Usagre (Badajoz) and Las Alpujarras (Granada) were submitted to Lead Isotopes analysis. These results were added to those available in the geo-chronological literature referred to the Almadén mining district (Ciudad Real), the largest concentration of cinnabar in the world, although with the oldest evidence of mining dated, at present, to the 8th century BC. The confrontation of the lead isotopic results of the samples from archaeological contexts and of the mineral deposits showed, firstly, the distinguishable lead isotopic composition of the main cinnabar mines studied and, secondly, the consistency of the isotopic composition of the archaeological Neolithic and Chalcolithic cinnabar samples with the Almadén district isotopic field. Based on the currently available isotopic data, it is proposed that the exploitation and the use as a pigment of cinnabar mineral from the Almadén district started, at least, in the late 6th millennium BC, being distributed through long distance exchange networks during the Neolithic and Chalcolithic periods.

Background: The important trecento Florentine artist Giotto (c. 1266-1337) is renowned for his naturalistic and realistic works in tempera and fresco. His innovative paintng style involved painting expressive, emotive faces and use of pictorial devices for depicting space. This report focuses on the analysis of the materials and methods used in a panel in the collection of the National Gallery of Art, Madonna and Child (1310/1315). Results: Giotto used inky washes under thin layers of egg tempera paint. Yellow iron earth and lead tin yellow are present in the paint used to depict the lining of the Virgin's mantle. SEM-EDX of one of the yellow pigments confirmed it is lead tin yellow type II, PbSn 1-x Si x O 3. The ratio of colorant to the glassy phase indicates this material was produced for use as a pigment rather than as a glass. Ultramarine was not used in this painting, azurite is the blue pigment. The azurite used here does not contain elemental impurities, however malachite and the rare green–blue mineral mixite, BiCu 6 (OH) 6 (AsO 4) 3 (H 2 O) 3 , are found in the blue paint.

Several spectroscopic techniques have been applied in order to characterize the polychrome pigments used in some religious sculptures, from the 13th to the 18th centuries, belonging to the cultural heritage of Extremadura (west of Spain). First, two energy‐dispersive X‐ray fluorescence portable devices were used. The measurements were carried out in situ, where the artworks were been restored. In addition to these nondestructive analyses, various samples with a millimeter size were taken from some of the sculptures and embedded in polyester resins. The stratigraphy of these fragments was observed through an optical microscope. Finally, they were analyzed using a scanning electron microscope in a low‐vacuum mode with two different detectors. Results show a wide range not only in pigments but also in the methods used in their realizations. Moreover, the variety of pigments found allows distinguishability from different restorations carried out along centuries.

In the sixteenth century, the Erzgebirge mountains were mined for mineral ores of cobalt and antimony that were used to make the blue pigment smalt, a potash glass, and yellow pigments based on lead-antimony oxides, respectively. By the beginning of the seventeenth century, these pigments had found a permanent place on the easel painter’s palette, smalt used in place of ultramarine and the antimonial compounds enlivening the yellows of the spectrum. Mining efforts also located sources for naphtha, and improvements in distillation would have allowed it (and other solvents) to be fractioned and purified for use as a solvent and diluent for oil paint. The mention of naphtha in treatises and color-sellers’ inventories  to its use in color making. Thinning paint allowed artists to use glazes of paint to lively, luminous, coloristic effect and made blending easier. These three discoveries contributed to the saturated colors characteristic of seventeenth-century painting and offered artists latitude in the ways they pursued their goal of imitative painting.

This publication, a slight revision of my MA thesis from 1967, is the first published report showing the modern Maya use of palygorskite (then called attapulgite), a clay mineral used by the ancient Maya to make Maya Blue, an unusual pigment that is resistant to weathering and retains it rich blue color over time. Most of the report is devoted to demonstrating that the potters of Ticul used palygorskite in their temper, and that they  recognized its unusual properties. The report suggests that nearby Sacalum and perhaps Ticul were sources of the pigment used to obtain palygorskite for Maya Blue since those communities are so close to Mayapan where the pigment was widely used. (In this report, II thought that Maya Blue was made locally and traded widely, but I no longer believe that this is the case.)

The use of watercolour red proved especially disconcerting for seventeenth-and eighteenth-century artists – it came in a wide range of costs, and with a dizzying list of names and shades according to the pigments used. On the economic and aesthetic choice the painter made also depended the staying power of the finished product. The cause of significant anxieties, it was nonetheless the reigning colour, not only because of the modern discovery of its primary status, but also because of traditional significance attached to it in the book industry, as well as in conventional architectural and military representations. This paper investigates what red signified, how its elusive powers were slowly tamed by modern standardization, and what its conventional uses meant for the European-wide dissemination of uninventive watercolour practices. Red pigments of vermilion, carmine, minium or madder, when mixed with linseed or safflower oil become durable on many counts. As oil paints, the amount of time the painter has to work them on the canvas is extended, their hue once dried lasts longer, their resistance to light or humidity is enhanced. But the same red pigments, mixed with a gum-arabic and water medium, prove more fickle. To apply watercolour in the early modern and modern period, the artist used the flick of an ente – a stick composed of two brush ends with one side for pigment, and one side for water, and which permitted little more than one attempt to get the gesture right before the paint dried on the paper. Watercolours rubbed off, faded in light and were degraded by humidity. However, what proved durable was the set of conventions that framed its practise, restrained experimentation, and reined in the rise of more creative and freer uses than those defined by its largely military and architectural uses. " Colour functions within semiotic codes that were developed by socio-cultural agents in response to the exigencies of specific times and places. Such exigencies – the Kairos of color – make color both a tremendous source of visual pleasure and of visual anxiety " (Feeser et al, 1). How exactly were the development, dissemination, and functions of watercolour practices influenced by this tension between visual pleasure and visual anxiety? As a medium primarily directed towards paper, and often used to colour what came out of the printing press, the history of watercolour use is inextricably linked to the circulation of information and knowledge. Who got to " define [colour], give it its meaning, construct its codes and values, establish its use " also got to define the level of objectivity that was ascribed to the information circulated in watercolour (Pastoureau, 10). The dizzying amount of shades available in the modern period meant that red was materially elusive. But for all its semiotic rebelliousness, the perception of watercolour red was greatly constrained by the tightly-knit conventions that had been created for military and architectural drawing. However, as a recently established primary colour, red also gained recognition as the colour with the strongest claim to symbolize importance and strategic use. And even when all other colours were scorned, red often remained as the pulsating heart of architectural and military drawings.

A multi-technique study on materials used for the painting “Cristo alla Colonna” by Luigi Bria (private collection, Cosenza, Italy) was carried out for the first time during the restoration plan. Pigments, binder media and raw materials used for the application of ground and priming layers were studied using optical (OM) and electronic microscopy equipped with energy dispersive spectroscopy qualitative microanalysis (SEM-EDS), infrared spectroscopy (FTIR) and gas chromatography coupled with mass spectrometry (GC/MS). The goal of this study was to characterize this canvas and to set up a scientific aid and guide for its restoration, taking into account the, severe damage not exclusively due to natural decay processes. Our data can provide information about historical and stylistic background as well as advises for correct planning of the cleaning procedures.

Pigments Checker is a collection of swatches of historical pigments that offers art professionals, conservation scientists, conservators and fine art photographers, a tool to evaluate and test their imaging and spectroscopic methodologies for pigment identification. " Pigments Checker Free Spectra Database " is an ongoing project that wants to thoroughly characterize each pigment in the collection with a series of spectroscopic and imaging techniques and to make the data open access. This paper presents the free and downloadable database of XRF spectra, adding to the reflectance spectral database already published. The XRF analysis is in agreement with the information provided by the pigments' manufacturers since all of the pigments have XRF spectra consistent with the expected elemental content reported in literature. In addition to elemental characterization by XRF, future analysis with Raman, FT-IR and XRD will be pursued in order to achieve a broader characterization of the pigments.

The social man creates or borrows practical procedures, and with them specific phrases. Unfortunately present literature often separates these phrases from the techniques in which the same phrases are used. This is the case of the colour term 'azure' and 'lapis lazuli' that denotes today an aggregate of minerals from which the pigment ultramarine 'blue' was extracted in the course of the Middle Ages. The present work collects well-established pieces of information from a multidisciplinary standpoint with the aim of highlighting the various social utilisations of ground lapis lazuli, or better, its 'blue' mineral called lazurite. New data is extracted from the Thesaurus Linguae Graecae, and Medieval Latin manuscripts (MSS) devoted to colour making. The oldest Western use of the pigment ultramarine 'blue' preceded of about seven centuries the first three 13th-14th century recipes, which describe the production of the pigment from lapis lazuli. This enormous time gap requires a new interpretation of the social mechanisms that transmit practical arts. Available chemical data refutes the hypothesis of a single mining supply source for archaeological findings of lapis lazuli, and new evidence demonstrates also that the phrase ultramarine 'blue' is strongly misleading. The term 'blue' became a basic colour term most likely in the early 15 th century England. Instead, the Medieval Latin word 'lazurum' and the corresponding Vernacular terms drew from lazurin, a 9 th century A.D. transliteration of the Greek λαζούρ (lazour), attested since the 4 th century A.D. The latter stemmed from the Persian colour term lājvard, which denoted lapis lazuli and other 'blue' substances. This study paves the way for the study of the intricate social utilisations of an 'azure' pigment that was successively called ultramarine 'blue', and on the first linguistic evidence of the term 'azure'.

Background: Since 2007, the research led on the Huaca Ventarrón site has allowed investigators to discover outstanding
wall paintings. These murals are one of the oldest examples of this artistic expression in the Andean area
and American continent (4000 BP). Analyses have given indications on the materials and techniques used by the first
painters, ancestors of a long pictorial tradition.
Results: Thanks to an archaeometric approach, combining observations and analysis (Optical Microscopy (OM),
Scanning Electron Microscopy and Energy-dispersive X-ray Spectroscopy (SEM–EDS), X-ray Fluorescence (XRF) and
Fourier Transform Infrared Spectroscopy (FTIR)), it was possible to characterize the colorant materials used in the two
constructive sampled phases. These materials are mineral pigments, iron oxides, clays and natural earth, mixed in
order to create a wide chromatic scale.
Conclusions: Through this research we were able to obtain the first analytical data concerning such ancient mural
paintings. It was very useful to comprehend the emergence of this artistic expression in Peru. These results open new
research perspectives as well about the origins of Prehispanic pictorial technology as about conservation of wallpaintings
in earthen architecture.

"Up until the date of this thesis in 1967, the palygorskite (previously called attapulgite) used in Maya Blue was unreported and unknown in the Maya area. This thesis demonstrated that it not only occurred in Yucatán, but that the potters of Ticul recognized its properties, called it sak lu’um (literally ‘white earth’) and used it as a critical ingredient in their temper for making pottery and medicinal uses. Besides the source of the mineral near Ticul mentioned here, this work first identified the town of Sacalum, Yucatán (a hispanization of the Maya word ‘sak lu’um’) as an important source of palygorskite.

This work provided the basis of two articles published subsequent to this thesis, and drew heavily from it:  “Sak lu'um in Maya Culture: and its Possible Relationship to Maya Blue” (1967) and  “Ethnomineralogy of Ticul, Yucatan Potters: Etics and Emics” (1971) . This thesis was seminal in my subsequent research dealing with different aspects of Maya Blue, and started me on a research agenda on Maya Blue that is still important now, some 45 years later. Most of my subsequent published papers on Maya Blue have already been posted on this page, but more will be forthcoming, and my research and writing on the subject continues. Many of the conclusions described here have been verified by others, but issues of the nature of the production of Maya Blue and whether the pigment or the palygorskite was transported have been shown to be much more complex than described in the thesis. Further, although certainly the Ticul/Sacalum area was an important source area for palygorskite, other occurrences of the mineral have been found. It is unclear whether any of these sources were ever a source of the clay used in the pigment, and if they were, when they were used."

Colours containing bright and saturated blue hues were popular for painterly effects in most of the Mediterranean cultures dating from the Bronze Age to the fall of the Roman Empire. Pigments providing the desired blue were produced from precious minerals such as azurite and lapis lazuli, but bright blue hues also came from pigments produced by merging other naturally occurring sources. This large group of synthetically-generated blue frits is referred to as Egyptian blue. Egyptian blue is a calcium copper tetrasilicate compound, a synthetic pigment made by heating a calcium compound (such as powdered limestone and sand rich in calcium carbonate) together with copper and quartz (fig. 1), although synthetic blue pigments based on cobalt are also known, so far mainly in Egypt (such as “Amarna-blue”). The hue of Egyptian blue pigments ranges from a saturated, almost black blue to light blue, bluish-green, and purple, each being dependent on the materials employed for its production and manufacturing process. Its material properties are crystal-like, resembling finely shattered glass. It ranges in saturation and brightness (which can be enhanced by secondary heating), and it has a relatively low covering power. It seems to have ceased being widely applied sometime after the fall of the empire, which added a certain mystery to it.

From the literature research review of studies that involved the physicochemical characterization of rock art paintings in Argentina and Chile, we evaluate the impact of this analytic approach in our understanding of these visual and material practices in the southern region of South America. We identify the techniques, protocols and sample preparation, the information obtained, and archaeological questions addressed with these analyses. Consequently, we propose the need for a microarchaeological approach. We stress the materiality and particularities of the rock art practice, as an action performed over continuously altered walls, which forms complex microstratigraphies. Moreover, we highlight the benefits of obtaining comparable results with the use of paintings on different supports and contexts to hold an Archaeology of Color that allows studying not only the meaning, but also understand the exploitation, production, and consumption of color, being the painted rock art one form of the final stage of a complex sequence related to color materials.

Authors: M. Aceto, E. Calà, A. Agostino, G. Fenoglio, M. Gulmini, A. Idone, C. Porter, C. Hofmann,  C. Rabitsch, C. Denoël, Christian Förstel, A. Quandt.

The traditional knowledge concerning the use of Tyrian purple in Late Antique and Medieval purple codices-those precious biblical texts written with noble metal inks on parchment dyed or painted with purple colourants-is here updated in view of new analytical evidence. Recent literature reports the analysis carried out on some purple codices, suggesting that Tyrian purple has not, if ever, been used in their making. A large number of purple codices has been considered in this work to elucidate the nature of the purple colour. Results have been discussed within the frame of previous information, thus covering a vast majority of the purple codices presently identified. In most of the instances the use of less expensive dyes such as folium or orchil is suggested. Moreover, analytical results from a non-invasive spectroscopic approach have been definitely confirmed by micro-invasive surface-enhanced Raman analysis performed on micro samples of purple parchment taken from two 6th century codices.

This paper presents the outcomes of a restoration project started from 2009 and finalized
in 2011 at the Pīr-i Hamza Sabzpūsh tomb of Abarqū, central Iran. The project comprised of
analytical studies and restoration works on the architectural decorations of the tomb consisting
of wall paintings and polychrome stuccoworks. Micro-Raman spectroscopy (μ-Raman)
and micro X-ray fluorescence (μ-XRF) analysis were used to compare the chemical and
mineralogical composition of the pigments used in the wall paintings and the stuccoworks of
the mihrab. The results showed that atacamite, huntite and ultramarine were green, white and
blue pigments respectively used on both wall paintings and the stuccoworks of the mihrab.
Furthermore, while red lead was used as red pigment on the mihrab, the red pigment of the
wall paintings was identified to be red hematite. In addition, the patterns of the wall paintings
were delineated with a black paint composed of carbon black. The different trace elements
associated with the paints established different sources of supplying pigments used in the
decorations. It is also shown that red lead was partially blackened likely due to the action
of air pollutants. Moreover, an omitted part of an inscription of the mihrab was discovered
during restoration works that contributed to re-date the stuccoworks to the second half of the
12th century. Finally, rejecting the current assumptions, which attribute the wall paintings
to the 14th century, it was proved that the wall paintings were the first decorations of the
tomb created prior to the second half of the 12th century. The current work contains also a
corrigendum to our previous study published on the decorations of the tomb.

A set of about 70 fresco samples made with pigments and binders typical of the Renaissance period in Rome has been characterized by LIBS, LIF and colorimetric measurements in order to build an as much as possible complete database. Aiming at providing the restorers and art historians with a useful tool for the study of ancient frescoes, the samples have been prepared in agreement with the Cennino Cennini recipes for both materials and procedures. Afterward, the obtained spectral data have been processed by means of multivariate analysis methods in order to find the most significant features that can help in fast characterization and recognition of real unknown specimens.

This collection presents state-of-the-art approaches to the use of inorganic raw materials in the period known as prehistory. It focuses on stone-tools, adornments, colorants and pottery from Europe, America and Africa. The chapters intimately merge archaeology, anthropology, geology, geography, physics and chemistry to reconstruct past human behaviour, economy, technology, ecology, cognition, territory and social complexity. The book represents a framework of raw material investigation for those working in science, regardless of the time period, region of the world or materials they are studying.

In 1988, the Analytical Research Laboratory of the Canadian Conservation Institute undertook the analysis of 13 wall painting fragments from the Magao and Bingling Temple Grottoes representing the range of pigment colors observed. Using various types of microscopy, x-ray diffraction, and Fourier transform infrared spectroscopy, the authors studied cross sectioned samples. (In a parallel study undertaken at the Dunhuang Cultural Relic Research Institution, 293 samples were studied.) They were unable to detect the presence of any binding media, but detected calcium oxalates in most paint layers, leading them to suspect that the paintings had been subject to microbiological deterioration. They identified hematite, azurite, red lead, copper compounds, a gold/silver alloy, and plattnerite pigments and found that the typical structure of the paintings was a supporting layer of clay over the grotto wall, a preparatory layer of clay and straw with calcium carbonate, and thin paint layers. (AATA Nos: 1999-92922 and 35-621; Abstractor: Rebecca Anne Rushfield)