The Royal Institute for Cultural Heritage (RICH) radiocarbon (14C) laboratory in Brussels, Belgium, has acquired experience for pretreating samples with 60 years of involvement in 14C dating, and the implementation of routine protocols. These procedures as applied to wood, seeds, charred materials, bones, ivory, textiles (silk, wool, cotton, linen), paper, shells, cremated bones, mortars, lead carbonates, sediments, etc. are described in detail in this paper. They are evaluated against reference materials.

Radiocarbon (14C) dating of protein-containing material (collagen, hair/wool, silk, leather) contaminated with extraneous carbon (e.g. humic substances) might result in unreliable dates when pretreated with the conventional but inadequate protocols. In this study cross-flow nanofiltration was applied to pretreated, protein-containing material. This method is able to remove low-molecular and high-molecular weight contaminants as demonstrated in previous studies. The sample quality improvement by cross-flow nanofiltration is verified by measuring the C:N ratio before and after nanofiltration. If the C:N ratio of the permeate (sample after cross-flow nanofiltration) falls within the C:N boundaries for uncontaminated wool/hair, silk and bone collagen, it is assumed to be contamination free. In our study, we focused on wool, silk, and collagen samples of known historical age. All samples treated by cross-flow nanofiltration effectively outputs C:N ratios within the expected range and yield for more accurate 14C date in agreement with historical expectations whereas bulk samples with C:N ratio out of the expected ranges, give either younger or older dates. We thus highlight both that C:N ratio is a good indicator of contamination and that cross-flow nanofiltration is an efficient method to treat protein-containing materials prior to 14C dating.

Lime burials are a characteristic phenomenon of the protohistoric funerary tradition on the Balearic Islands. At Cova de Na Dent, six samples, representing the entire stratigraphy of the lime burial, were taken for analysis. The radiocarbon dates suggested that the lowest levels of the burial were Late Bronze Age. This is in contradiction with the general belief that the lime burials are a late Iron Age phenomenon. Therefore, a new analysis strategy is put forward, focusing on the so-called 1st fraction, the first CO2 released during the acid lime reaction, which is supposed to be free of fossil carbon. The analysis demonstrates the impossibility to eliminate the fossil carbon fraction completely. This is probably due to the different geological formation of the local limestone deposits (ancient reef barriers) compared to the previous lime burials of Mallorca all coming from mountain areas. 14C analysis from a cremation layer without lime at the onset of the lime burial reveals an Iron Age origin of the Cova de Na Dent lime burial.

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. The 14C dates on the lime suggest an earlier chronology for this ritual, starting in the Bronze Age, as generally is accepted.

An overview will be presented of stable isotope data (δ13C and δ15N) available from animal and human bones from Roman to post-Medieval Belgian sites. The data will be used to assess trends in the human diet and evaluate the possible impact of reservoir effects originating from the consumption of fish derived from marine or freshwater environments. Historical and archaeozoological data demonstrate drastic changes in fish consumption throughout the last 2 millennia and thus suggest that fluctuations through time of the impact of the reservoir effects can be expected. However, the present stable isotope data set does not support this suggestion.

Based on radiocarbon and optically stimulated luminescence (OSL) results obtained in the last 5 yr, this paper discusses the absolute chronology of the formation of one of the largest sand dunes within NW Belgium, the Great Ridge of Maldegem-Stekene. Multiproxy analysis of 6 sedimentary sequences points to a complex formation history covering the entire Late Glacial. Dry phases, characterized by eolian deflation and sedimentation, alternated with wet phases in which numerous mostly shallow dune slacks were filled with freshwater. The latter reached their highest water level during the first half of the Allerød, attracting both animals (e.g. European elk) and humans (Federmesser hunter-gatherers). Near the end of the Allerød, all dune slacks finally disappeared as they were filled in with windblown sand ("coversand"), likely forcing prehistoric hunter-gatherers to leave the area.

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.