Raman microscopy and x-ray fluorescence analysis of pigments on medieval and Renaissance Italian manuscript cuttings.

Italian medieval and Renaissance manuscript cuttings and miniatures from the Victoria and Albert Museum were analyzed by Raman microscopy to compile a database of pigments used in different periods and different Italian regions. The palette identified in most manuscripts and cuttings was found to include lead white, gypsum, azurite, lazurite, indigo, malachite, vermilion, red lead, lead tin yellow (I), goethite, carbon, and iron gall ink. A few of the miniatures, such as the historiated capital "M" painted by Gerolamo da Cremona and the Petrarca manuscript by Bartolomeo Sanvito, are of exceptional quality and were analyzed extensively; some contained unusual materials. The widespread usage of iron oxides such as goethite and hematite as minor components of mixtures with azurite is particularly notable. The use of a needle-shaped form of iron gall ink as a pigment rather than a writing material was established by both Raman microscopy and x-ray fluorescence spectroscopy for the Madonna and Child by Franco de' Russi.

Spectroscopic investigations of Bourdichon miniatures: masterpieces of light and color.

Metallic bismuth, pyrite (FeS2), and specular hematite (Fe2O3) were found to have been used extensively on two miniatures taken from the Book of Hours of Louis XII by Jean Bourdichon, painter at the Royal Court of France between the end of the 15th and the beginning of the 16th centuries. These unusual materials were identified, together with thirteen other more traditional pigments and dyes, by Raman microscopy and X-ray fluorescence. Pyrite was found in many areas, suggesting that it may have been deliberately added as a pigment. The luminary quality of both miniatures was enhanced by the extensive use of shell gold throughout, but other less common materials such as specular hematite and mosaic gold were also utilized. Metallic bismuth was used, alone or in admixture with other pigments, to create a soft gray color. Its identification as a paint material was complemented by the study of the optical and visual properties of standard samples of metallic bismuth and several bismuth compounds. Evidence for the use of a bismuth pencil was also found.

Correction to 'New genetic and morphological evidence suggests a single hoaxer created 'Piltdown Man''.

[This corrects the article DOI: 10.1098/rsos.160328.].

Raman microscopy of Greek icons: identification of unusual pigments.

Five Greek icons, made between the 15th and 18th centuries and now belonging to the Victoria and Albert Museum collections, were analysed by energy-dispersive X-ray fluorescence (EDXRF), optical microscopy and Raman microscopy in order to determine the stratigraphy of the artworks and the identity of the pigments used. Together with common pigments, such as red lake, vermilion, red lead, red iron oxide, orpiment, yellow ochre, lead white, chalk, gypsum, anhydrite, Prussian blue, indigo and a copper-containing green, a few unusual materials were identified, specifically pararealgar (a yellow arsenic sulphide, As4S4), its precursor the chi-phase, and lead tin yellow type II (PbSn(1-x)SixO3). Attention is drawn to the complementarity of the techniques used for the pigment identifications.

Raman spectroscopy analysis of pigments on 16-17th c. Persian manuscripts.

The palette of four Persian manuscripts of the 16th and 17th centuries were established by Raman microscopy to include lazurite, red lead, vermilion, orpiment, a carbon-based black, lead white, malachite, haematite, indigo, carmine and pararealgar. The first five pigments were identified on all four manuscripts, as previously found for other Islamic manuscripts of this period. The findings were compared with information available in treatises on Persian painting techniques. Red lead, although identified on all of the manuscripts analysed in this study as the main red pigment, is seldom mentioned in the literature. Two unusual pigments were also identified: the intermediate phase between realgar and pararealgar in the manuscript Timur namah, and carmine in the manuscript Shah namah. Although the established palette comprises few pigments, it was found that the illuminations were enhanced by the use of pigment mixtures, the components of which could be identified by Raman microscopy.

Analysis of yellow "fat" deposits on Inuit boots.

Irregular residues of a yellow deposit that was assumed to be seal fat used for waterproofing were observed in the creases of the outer surface of a pair of Inuit boots from Arctic Canada. A sample of this deposit detached from one of these areas on these boots was examined initially by FT-Raman microscopy, from which interesting and rather surprising results demanded further analysis using FT-IR and GC-MS. The non-destructive Raman spectroscopic analysis yielded spectra which indicated the presence of a tree resin from the Pinaceae sp. The Raman spectra were also characteristic of a well-preserved keratotic protein and indicative of adherent skin. Subsequent FT-IR spectroscopic analysis supported the attribution of a Pinaceae resin to the yellow deposit. GC-MS analysis of the same deposits identified the presence of pimaric, sandaracopimaric, dehydroabietic and abietic acids, all indicative of an aged Pinaceae resin. These results confirmed that the Inuit people had access to tree resins which they probably used as a waterproofing agent.

Pigment identification by spectroscopic means: evidence consistent with the attribution of the painting Young Woman Seated at a Virginal to Vermeer.

Technical examination of the painting Young Woman Seated at a Virginal by cross section and polarized light microscopy, chemical tests, surface microscopy, energy-dispersive X-ray analysis, and Raman microscopy has led to the identification of the pigments lead tin yellow (type I), lazurite, vermilion, calcite, lead white, red and yellow iron oxides, umber, lamp black, and green earth on the canvas. These pigments are entirely typical of Vermeer's palette and are consistent with a large body of other technical and art historical findings on paintings by Vermeer and other Dutch 17th century artists. While not authenticating the painting as being by Vermeer, the results provide further critical material that is consistent with this attribution. This case study also provides an opportunity to outline the role of analytical and forensic sciences in the examination and attribution of art objects.