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The Raman spectra of nine variants of 'verdigris' (organo-copper complexes) synthesized recently by different methods have been measured at room temperature and at 150 K. The spectra are all characterized by a strong band at ca 2935 cm −1 and weaker bands at 3010, 2985, 2935, 1550, 1445, 1415, 1350 and 940 cm −1 at both temperatures; the majority of spectra also feature bands at 220 and 140 cm −1 . The features in the 3000-4000 cm −1 and 900-50 cm −1 regions of the spectra show the greatest differences from sample to sample: those in the high wavenumber region relate directly to the nature of the hydrogen bonding in each sample, while those in the lower region reflect the variations in the Cu-O bonding and crystal structures of each sample. The characteristic bands present in the 900-3000 cm −1 region are sufficient for the identification of a sample as a particular form of verdigris.

We report the compressibility of the stoichiometric hexagonal ␦ phase of MoN that is a well-known hard material that becomes superconducting below T c ϭ12 K. The measured bulk modulus is K 0 ϭ345(9) GPa and K 0 Јϭ3.5(3). We also report the compressibility of the non-stoichiometric cubic B1 structured ␥-Mo 2 N phase, that has a lower bulk modulus ͓K 0 ϭ301(7) GPa, assuming K 0 Јϭ4]. The difference in bulk modulus is due to the difference in structure and the cohesive energy between the two phases.

The King George III copy of the Gutenberg Bible, held at the British Library, has been analyzed using Raman spectroscopy to determine the palette of pigments used in the illuminations on this work. The palette is found to comprise cinnabar/vermilion, lead tin yellow (type 1), carbon-based black, azurite, malachite, an organo-copper complex (a "verdigris"), calcium carbonate (chalk), gypsum, gold leaf, and basic lead carbonate ("lead white"). This is in agreement with contemporary descriptions of the pigments used for the illuminations. One pigment could not be identified, specifically the organic dark red/purple color used for the foliage. The palette of this copy of the Gutenberg Bible has been compared with those used for six other copies, held at Eton College and Lambeth Palace, England, the Bibliothèque Mazarine and the Bibliothèque nationale de France, and the Staatsbibliothek zu Berlin and the Niedersachsische Staats- und Universitatsbibliothek (SUB) Göttingen, Germany. The palettes are shown to be similar to one another, even though the styles of the primary illuminations differ. The two Gutenberg Bibles held in Germany, printed on vellum, have the more expensive palettes, which include lazurite. The SUB Göttingen copy has the most extensive palette with 16 pigment-related materials having been identified.