When archaeologists discuss ‘ancestor cults’ or ‘ancestor veneration’, what this might entail in practice usually remains vague, leading to charges that the concept of ‘ancestors’ is often applied generically. In this article, the authors combine bioarchaeological, taphonomic, radiocarbon, and isotopic studies to explore the ritual practice of the selective retention, curation, and deposition of a group of human crania and mandibles. Between 5500–5400 bc, Neolithic people at Masseria Candelaro (Puglia, Italy) deposited broken crania and mandibles from about fifteen individuals in a heap in the centre of the village. These individuals were mostly probable males, collected over the course of two centuries and actively used, with their deposition marking the final disposal of a ritual collection. The motivations for the curation of cranial bone are investigated through comparison with archaeological and ethnographic examples, advancing an interpretation of ritual practice directed towards ancestors.

Kaolinite: alkali halide intercalates have been successfully prepared by grinding the salt with kaolinite in the absence of water. Rate of intercalation is shown to correlate negatively with melting point of the salt. The basal dimensions of the intercalates increase with increasing size of the ion. As shown recently for kaolinite: NaCl intercalate, the layered structure survives the dehydroxylation of the kaolinite at 500°–600°C, at which point the excess alkali halide can be removed by rinsing to give an XRD-amorphous material. This amorphous material, of approximate stoichiometry MAlSiO4, reacts at surprisingly low temperatures to give crystalline phases, apparently of the same stoichiometry, with structures closely related to eucryptite (M = Li), carnegieite (M = Na), kalsilite (M = K), and leucite (M = K, Rb, Cs). The relationships between the structures of the reaction products are discussed.

Bulk and size-fractionated kaolinites from seven localities in Australia as well as the Clay Minerals Society Source Clays Georgia KGa-1 and KGa-2 have been studied by X-ray diffraction (XRD), laser scattering, and electron microscopy in order to understand the variation of particle characteristics across a range of environments and to correlate specific particle characteristics with intercalation behavior. All kaolinites have been intercalated with N-methyl (NMF) after pretreatment with hydrazine hydrate, and the relative efficiency of intercalation has been determined using XRD. Intercalate yields of kaolinite: NMF are consistently low for bulk samples that have a high proportion of small-sized particles (i.e., <0.5 µm) and for biphased kaolinites with a high percentage (>60%) of low-defect phase. In general, particle size appears to be a more significant controlling factor than defect distribution in determining the relative yield of kaolinite: NMF intercalate.

Kaolinite:NaCl intercalates with basal layer dimensions of 0.95 and 1.25 nm have been prepared by direct reaction of saturated aqueous NaCl solution with well-crystallized source clay KGa-1. The intercalates and their thermal decomposition products have been studied by XRD, solid-state 23Na, 27Al, and 29Si MAS NMR, and FTIR. Intercalate yield is enhanced by dry grinding of kaolinite with NaCl prior to intercalation. The layered structure survives dehydroxylation of the kaolinite at 500°–600°C and persists to above 800°C with a resultant tetrahedral aluminosilicate framework. Excess NaCl can be readily removed by rinsing with water, producing an XRD “amorphous” material. Upon heating at 900°C this material converts to a well-crystallized framework aluminosilicate closely related to low-carnegieite, NaAlSiO4, some 350°C below its stability field. Reaction mechanisms are discussed and structural models proposed for each of these novel materials.

Large stratovolcanoes in the Cascade Range have high equilibrium-line altitudes that support glaciers whose Holocene and latest Pleistocene advances are amenable to dating. Glacier advances produced datable stratigraphic sequences in lateral moraines, which complement dating of end moraines. New mapping of glacial deposits on Mount Rainier using LIDAR and field observations supports a single latest Pleistocene or early Holocene advance. Rainier R tephra overlies deposits from this advance and could be as old as >11.6 ka; the advance could be of Younger Dryas age. Radiocarbon ages on wood interbedded between tills in the lateral moraines of Nisqually, Carbon, and Emmons glaciers and the South Tahoma glacier forefield suggest glacier advances between 200 and 550 CE, correlative with the First Millennium Advance in western Canada, and during the Little Ice Age (LIA) beginning as early as 1300 CE.

These results resolve previous contradictory interpretations of Mount Rainier's glacial history and indicate that the original proposal of a single pre-Neoglacial cirque advance is correct, in contrast to a later interpretation of two advances of pre- and post-Younger Dryas age, respectively. Meanwhile, the occurrence of the pre-LIA Burroughs Mountain Advance, interpreted in previous work as occurring 3–2.5 ka, is questionable based on inherently ambiguous interpretations of tephra distribution.

Helium or neopentane can be used as surrogate gas fill for deuterium (D2) or deuterium-tritium (DT) in laser-plasma interaction studies. Surrogates are convenient to avoid flammability hazards or the integration of cryogenics in an experiment. To test the degree of equivalency between deuterium and helium, experiments were conducted in the Pecos target chamber at Sandia National Laboratories. Observables such as laser propagation and signatures of laser-plasma instabilities (LPI) were recorded for multiple laser and target configurations. It was found that some observables can differ significantly despite the apparent similarity of the gases with respect to molecular charge and weight. While a qualitative behaviour of the interaction may very well be studied by finding a suitable compromise of laser absorption, electron density, and LPI cross sections, a quantitative investigation of expected values for deuterium fills at high laser intensities is not likely to succeed with surrogate gases.