Faience objects produced from the fourth millennium BC in ancient Egypt are considered as the first high-tech ceramics in human history. Despite extensive studies on manufacturing technology, many aspects of this complex technology remain a mystery and there is no methodology in place to unravel the techniques of Egyptian faience object production. Detailed studies presented herein fill the gaps, verifying standing opinions and allowing certain aspects of faience manufacturing technology to be reconstructed. The object of this innovative investigation is a hemispherical faience bowl discovered by archaeologists excavating a Ptolemaic workshop district at the site of Tell Atrib in the southern Nile Delta. The multiproxy analysis included the application of specialised software and preparation techniques coupled with complementary methods of light and digital microscopy, SEM with EDS, XRD, STA with EGA, as well as image analysis. Sources of raw and accessory materials (mineral and organic binders, fluxes, colourants) used for preparing the silica paste and glaze slurry were determined. The results helped to reconstruct how the raw material was prepared and how faience vessels were made. The bowl was moulded by compression using a two-part mould. The moulded and dried bowl was then covered by glaze slurry using the application method. A synthetic colourant, Egyptian Blue, was probably used to colour the glaze. The item was fired once at a temperature of 1050–1150 °C. Oxidised conditions were maintained in the kiln during the firing process and firing at the maximal temperature was relatively short. Application of the multiproxy approach has shed light on the technological aspects of faience bowl manufacturing. The obtained results have confirmed the usefulness of the comprehensive methodology that was applied for the reconstruction of particular manufacturing stages of faience objects.
Interstratif ied serpentine-sm ectite was found in the fine-grained fraction of altered metasomatic contact biotite-schists developed between serpentinite and granite-type rocks (Lower Silesia ophiolite sequence, Poland). Ni-rich serpentine-smectite is R0-interstratified lizardite (0.80)stevensite (0.15)-vermiculite-like (0.05), with a coherent scattering domain (csd) of 5 layers (mean value). The Mg-rich variety of serpentine-smectite is R1 lizardite (0.80)-stevensite (0.20) with a csd size of 7 layers (mean value). A transmission electron microscope study revealed complex layer relationships, with zones composed of various serpentine-smectite packets having lizardite/ smectite ratios of 3:1, 2:1, 1:1, 4:1 and scarce serpentine segregations. In both cases, the serpentine-smectites appear to be late products of alteration of the parent biotite-schist.Experimental and calculated positions and intensities of reflections of the ethylene glycol-saturated, heated (250ºC, thermal stage), and air-dried samples are in good agreement. Calculated X-ray diffraction patterns for interstratified glycolated and anhydrous serpentine-smectite are included in the Appendix.
Coarse-grained vermiculite from a serpentinite-pegmafite thermal zone displays a rational series of narrow 14.4 A basal reflections and an unusual broad 28 A peak. X-ray diffraction simulations and fitting techniques show that the 28 ,~ peak is related to 28 .~ domains consisting of elongated 2:1 layers of different lengths. The domains are located at the crystal edges of the vermiculite.
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