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The Naples Yellow pigment was apparently used for the first time by the Egyptians, as a glass-colouring agent. Also known in the Mesopotamian and Roman cultures, the recipe was lost in Western Europe between the fourth and the 16th centuries ad. The recipe for the production of lead antimonate recently discovered in the ‘Codice Calabranci’ (second half of the 15th century) at Montelupo, a small town near Florence (Italy) known for its large-scale ceramic production, possibly represents the very first evidence of the reintroduction of Naples Yellow in Western Europe after a long period of absence. The major-element composition of the lead antimonate pigment in the Montelupo ceramics of the 15th and 16th centuries is in accordance with the ‘Codice Calabranci’ recipes. Lead isotope analyses indicate that the lead used to produce the yellow pigments and the underlying glaze of the Montelupo majolica did not come from the Tuscan mining districts, but was possibly imported via Venice from more distant lead sources in Turkey.

The mineralogy, petrography and major- and trace-element composition of iron ores from Elba Island (Tuscany, Italy), one of the most important iron sources in the Mediterranean area since the first millennium bc, revealed that hematite-rich ores display prominent enrichments in W and Sn (up to 4950 μg g−1 and 8400 μg g−1, respectively). These two elements are hosted by tiny grains of W–Sn mineral phases (ferberite, scheelite and cassiterite) that are disseminated throughout the hematite matrix. A comparison with iron ores from many Italian and European localities (most of which were exploited in ancient times) suggests the uniqueness of the geochemical pattern of Elba Island hematite-rich ores (i.e., high W and Sn, low Mo and low Cu, Pb and Zn). We suggest that this geochemical signature may represent a new provenance marker not only for discarded ore at smelting/smithing sites, but, possibly, also for metallurgical slag and smelted metal produced in the chaine operatoire of the iron process.

The Istituto di Geoscienze e Georisorse (IGG), on behalf and with the support of the International Atomic Energy Agency (IAEA), prepared eight geological materials (three natural waters and five rocks and minerals), intended for a blind interlaboratory comparison of measurements of boron isotopic composition and concentration. The materials were distributed to twenty seven laboratories - virtually all those performing geochemical boron isotope analyses in the world -which agreed to participate in the intercomparison exercise. Only fifteen laboratories, however, ultimately submitted the isotopic and/or concentration results they obtained on the intercomparison materials. The results demonstrate that interlaboratory reproducibility is not well reflected by the precision values reported by the individual laboratories and this observation holds true for both boron concentration and isotopic composition. The reasons for the discrepancies include fractionations due to the chemical matrix of materials, relative shift of the zero position on the δ11B scale and a lack of well characterized materials for calibrating absolute boron content measurements. The intercomparison materials are now available at the IAEA (solid materials) and IGG (waters) for future distribution. L'Istituto di Geoscienze e Georisorse (IGG), pour le compte et avec le soutien de l'Agence Internationale de l'Energie Atomique (AIEA), a prepare huit materiaux geologiques (trois eaux naturelles et cinq roches et mineraux) destines a la conduite d'une comparaison en aveugle des mesures de composition isotopique et de concentration du bore entre differents laboratoires. Vingt-sept laboratoires -pratiquement tous ceux qui travaillent sur les isotopes du bore en geochimie - ont accepte de participer a cette intercomparaison, mais quinze seulement ont finalement envoye leurs donnees de composition isotopique et/ou de concentration du bore. Les resultats demontrent que la precision des valeurs indiquee par les laboratoires reflete mal la reproductibilite entre laboratoires des mesures de composition isotopique comme de concentration du bore. Les raisons de ces discordances peuvent comprendre l'existence de fractionnements isotopiques dus aux matrices chimiques des materiaux, un deplacement relatif du zero de l'echelle de δ11B, ainsi que le manque de materiaux bien caracterises pour calibrer les mesures de concentration du bore. Les materiaux utilises pour l'intercomparaison des mesures sont maintenant a disposition a l'AIEA (materiaux solides) et l'IGG (eaux) pour etre distribues.