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This work presents the results of the study of a fragment of architectural terracruda sculpture from the Buddhist archaeological site of Tepe Narenj (Kabul, Afghanistan, 5 th -9 th centuries) through X-ray microtomographic analysis. This technique offers great potential for the study of artworks that, due to their nature, state of conservation or relevance, do not allow for destructive analysis. The results have provided useful data

We have studied the morphology and electronic structure of cluster-assembled carbon films containing nickel and titanium nanoparticles by structural probes ͑transmission electron microscopy͒ and electronic spectroscopies ͑x-ray absorption, Auger spectroscopy, and electron energy loss͒. Vibrational characteristics of the surface have been investigated using high resolution electron energy loss spectroscopy. Nanocomposite carbonmetal films have been grown by supersonic cluster beam deposition of carbon clusters produced in the presence of finely dispersed metal catalysts. Characterization has been performed on pristine, annealed ͑at 560 K in vacuum͒, and H 2 exposed (p H 2 ϭ1 mbar) samples. The nanocomposite films are characterized by metallic clusters embedded in a matrix of nanostructured carbon. The carbon structure at the nanoscale depend upon the type of metallic species. The electronic properties of the as-deposited films do not show any evidence of carbide formation. Thermal treatment and H 2 exposure procedures have different effects on the electronic features inducing a certain degree of bond ordering and a decrease of the available sp 2 sites, respectively.

The obsidian of Sierra de las Navajas is well known for its green color and gold hue. In order to relate these features with compositional and microtextural characteristics, we have carried out a microanalytical study by Wave Dispersion System associated to Electron Probe Micro-Analyzer, Scanning Electron Microscope observation, and X-rays micro-tomographic analyses of samples showing different colors (dark to light green, sometimes with bands of different color intensity) and hues (changing, uniform, no hue). In accordance with previous studies, the green color of the obsidian seems to be related to a high iron content, probably in its reduced state. However, no significant difference in composition occurs between dark and light green samples. The SEM observation and microtomographic study revealed the absence of microcrystals and the occurrence of vesicles of different size, shape, and orientation. Lighter green colors are shown by highly vesiculated surfaces, whereas non-vesiculated samples are darker. On the surfaces with a high concentration of coarse vesicles, a uniform golden hue is observed. Decreasing vesiculation gives a hue changing with the angle of incident light. However, when the vesicularity approaches zero, no hue is visible. The iso-orientation of vesicles along preferential directions and their distribution in bands determine the variation in color intensity and hue on differently oriented surfaces. Microvesiculation also influences other characteristics that were important features for the use of obsidian in the past, such as fracture, transparency, and roughness.