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The microstructure and some magnetic properties of the bulk amorphous [([Fe.sub.0.61] [Co.sub.0.10] [Zr.su.0.025] [Hf.sub.0.025] [Ti.sub.0.02] [W.sub.0.02] [B.sub.0.20).sub.100 -1-x] [Y.sub.x] (x = 0 or 2) alloys are studied. The as-quenched and annealed at 720 K for 15-min alloys, well below the crystallization temperature, as confirmed by X-ray diffraction and Mossbauer spectroscopy studies, are fully amorphous. The investigated alloys are soft magnetic ferromagnets and exhibit relatively high magnetic susceptibility at low magnetic fields. However, the alloys show broad disaccommodation spectra characteristic of amorphous materials. The intensity of disaccommodation distinctly decreases after the addition of 2 at. % of Y to the amorphous [Fe.sub.61] [Co.sub.10] [Zr.sub.2.5] [Hf.sub.2.5] [Ti.sub.2] [W.sub.2] [B.sub.20] alloy and also after annealing at 720 K for 15 min. From the analysis of disaccommodation curves, the average activation energies of elementary processes are estimated. The obtained values of the activation energies, equal to about 1.2 eV, and preexponential factor in Arrhenius law in order of [10.sup.-15] 's indicate that observed disaccommodation phenomenon is connected with the ordering of atom pairs near free volumes. In higher magnetic fields, the magnetization fulfils M/Ms ~ 1/[[mu].sub.0] H law, pointing out the presence of quasi-dislocation dipoles with the width lower than the exchange length. After the addition of yttrium to the amorphous [Fe.sub.61] [Co.sub.10] [Zr.sub.2.5] [Hf.sub.2.5] [Ti.sub.2] [W.sub.2] [B.sub.20] alloy and the annealing of the samples at 720 K for 15 min, we observe the decrease of the quasi-dislocation dipoles width. Index Terms--Bulk amorphous materials, magnetization processes, Mossbauer spectroscopy.

The authors describe clay features dating from c. 34-23 000 years ago discovered in a stratified occupation sequence in a Greek cave. The clay was brought from outside the cave, puddled with water and shaped into shallow basins. Laboratory analyses have shown that these clay features were burnt. This together with the occurrence of fragments of wood ash and phytoliths lying on their surfaces suggest that these features were hearths used for cooking, including the roasting of wild grasses. Keywords: Upper Palaeolithic, Aurignacian, Greece, hearth, clay structures., Introduction Hearth structures are probably one of the first expressions of space-specific skills. Building a fireplace is a sign of permanence. Such structures are used repeatedly and can survive beyond [...]