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In order to verify correct labeling and purity of natural lacquer ingredients sold today, 66 resins, gums and oils were analyzed by THM-GC/MS and compared with non-commercial reference samples. 21 deviations were found, indicating an adulteration or mislabeling of a resin. Many of the deviations occurred in sandarac resin, traditionally harvested from Tetraclinis articulata (Vahl) Mast., which seems to have another composition today than historically. Differences between both types were persistent through artificial aging. This study comprised one freshly harvested sandarac resin, as well as several specimens of historical collections, as reference material for Tetraclinis articulata. The currently sold sandarac was compared with the Tetraclinis articulata references, and with resins from the genera Agathis, Juniperus and Callitris, but its botanical source was not revealed.

This study focuses on the very beginning of lacquerware production with chinoiserie decoration in Spa from the end of the seventeenth century to the third quarter of the eighteenth century. Through an interdisciplinary approach, the historical and material-technical context of this important historical lacquer production is elucidated. Archival research was conducted along with a stylistic study of thirty objects, mainly boxes. Furthermore, seventeen of the objects from this study group were chemically analysed for their organic ingredients, pigments and metal applications.

A set of 19th-century furniture in black lacquer, on papier-mache or on turned wood, has been subjected to an in-depth observational, historical and chemical study. The results show four different technological approaches: two for the papier-mache objects and two for the wooden chairs. The cyclic labour-intensive lacquering procedure of repeated stoving and polishing lacquer on papier-mache with mother-of-pearl inclusions is reflected in the cross-sections. Pinaceae resin and heated oil are frequently found, conform with surviving recipes. A variant of the old form of varnish', as historically described, was likely used. In the two pairs of wooden chairs, the lacquer layers are thinner than on the papier-mache items. They contain copal and show different stratigraphies. These observations can be the starting point to relate technological and chemical variations to different origins. New art historical findings on lacquer production and trade in England, France and Belgium, and the study of contemporary recipes, frame the analytical results in a historical context. [GRAPHICS] .

Lime burials are a characteristic phenomenon of the protohistoric funerary tradition on the Balearic Islands. At Cova de Na Dent, a lime burial has been sampled for analysis. The lime burial was made up of lime and fragmented bones. Six layers were sampled and described in the laboratory according to their color, the consistency of the deposition, and the aspect and quantity of the bone fragments. Bone samples and lime were dated. The lime was analyzed by using petrographic analysis, X-ray diffraction, FTIR spectroscopy, and simultaneous thermal analysis. The results show that the bones were cremated in the presence of crushed rock carbonate. The14C dates on the lime suggest an earlier chronology for this ritual, starting in the Bronze Age, as generally is accepted.

Traditionally, the Balearic so-called 'quicklime burials' of the Iron Age have been considered to be inhumations in quicklime. The general appearance of the bones, however, resembles more closely that of cremated bones. Laboratory tests reveal that the observed features of the bones from these burials, including cracks, thumbnail fractures and warping, cannot be explained by an inhumation in quicklime. The d 13 C value, Fourier transform infrared spectra, SF values and the low carbon content of the apatite moreover indicate a thermal manipulation of the bones. The 14 C content is depleted with regard to the accepted archaeological age of the sample, which can best be explained by carbon exchange between bio-apatite and fossil CO2 released during the heating of limestone. This implies that the Balearic 'quicklime burials' must be interpreted as an elaborate cremation practice in presence of limestone. Copyright © 2013 John Wiley & Sons, Ltd.

In order to optimize chromatographic analysis of European lacquer, thermochemolysis temperature was evaluated for the analysis of natural resins. Five main ingredients of lacquer were studied: sandarac, mastic, colophony, Manila copal and Congo copal. For each, five temperature programs were tested: four fixed temperatures (350, 480, 550, 650 degrees C) and one ultrafast thermal desorption (UFD), in which the temperature rises from 350 to 660 degrees C in 1 min. In total, the integrated signals of 27 molecules, partially characterizing the five resins, were monitored to compare the different methods. A compromise between detection of compounds released at low temperatures and compounds formed at high temperatures was searched. 650 degrees C is too high for both groups, 350 degrees C is best for the first, and 550 degrees C for the second. Fixed temperatures of 480 degrees C or UFD proved to be a consensus in order to detect most marker molecules. UFD was slightly better for the molecules released at low temperatures, while 480 degrees C showed best compounds formed at high temperatures.

The Balearic quicklime burials of the Iron Age have been radiocarbon dated. Because the bones found are unsuitable for dating, lime was dated using the titration method, with results indicating that in some samples there is still fossil limestone carbonate present, while other samples suffered from recarbonation. Nevertheless,14C dates on lime and organic matter agree when both arc present. The titration method allows calculating a consensus value.