Folia archeologica 45.

Tóth Endre: Dr. Soproni Sándor szakirodalmi munkássága

PALAEOLITHIC TOOLS 4,'i containing two-phase inclusion at room temperature (no. 1.) was placed into refrigerator at +2 - +6 °C for 12 hours, after placed into gemstone microscope it was visible that the inclusion formerly containing large volumes of gas became heterogeneous, and liquid CO appeared in a sickle-form rim between the water and the gaseous phase. By slow warming, the volume of this new phase decreased. Later on, water vaporisation phenomena prevented further observations. This experiment has at least proved the presence of phases rich in CO,,. In the other inclusions containing less CO (and probably other constituents like CH () the exact phase composition could lie only determined by systematical investigations, which is not possible given the archaeological character of the samples. The observ ed fluid inclusion types are summarised on Table 2. The following groups could be separated: A. Samples without fluid inclusions (2, 5, 6, 9, 14) The above pieces contain no observable fluid inclusions within the applied investigation tecnnique or other interior characteristic features. The raw material of these items must have been very clear large (min. 150-200 g) rock crystal or its fragment. It can be, however, connected to the other samples as an inclusion-free part of a major piece from the other types. Bl. Two-phase inclusions with equal phase ratio in clear quartz (Sample 10.) Inclusions with 10-5 vol. % gaseous phase with nearly equal phase ratio. B2. Two-phase inclusions in troubled quartz (Sample 11.) Inclusions with 10-5 vol. % gaseous phase with nearly equal phase ratio. On the basis of its appearance, the piece could be part of a "root" of an overgrown specimen or part of a quartz lens. CI. Samples with two phase inclusions with changing ratio of gas volume (100-80 vol. %, 60-30 vol. %, 10-5 vol. %); samples 7, 3, 8. The above pieces contain characteristic two-phase inclusions with different generations containing a decreasing ratio of gas / liquid towards the younger generations of inclusions. C2. Two phase inclusions (witli 100-80 vol. % and 10-5 vol. % gaseous phase, respectively); sample 1. C3. Two phase inclusions (with 100-80 vol. % gaseous phase); sample 13. I). Samples with two phase inclusions with changeable vol. % gaseous phase, occasionally witli liquid CO,, (samples 8, 13) Probable origin of the samples Grown-up quartz crystals are known within the Carpathian Basin and its immediate surroundings are found in various geological circumstances. Genetical comparison of this minerals can exclude certain possibilities which can lead us nearer to establish reliably the provenance of the archaeological rock crystal pieces. Main genetical type groups of quartz crystal are as follows: 1. Magmatic /rock forming/ quartz Quartz component of acidic magmatic rocks (e.g., granite): typically small, few cms large, milky white or non-transparent due to millions of inclusions in the jum range. Occasionally some volcanic rocks can also contain euhedral "clihexagonal" quartz, e.g. rhyolite or rhyolite tuff. The dimensions of these can be I -2 cms ancf in all instances they are troubled clue to very small glass or liquid-gas inclusions which can be easily identified. For the production of stone artefacts, these quartz crystals are not suitable.