No abstract

In this study the new mineralogical and geochemical evidence for the reason behind intensive resin production in trees and the formation of Indonesian resin deposits is presented. The analysed specimens of the “Indonesian amber” were subjected to the following comprehensive investigations: PAS, IR, RS XRD and SEM-EDS. It was found that the resins are originated due to intensive volcanic activity. Based on spectroscopic investigations, “Indonesian amber” was assigned to the glessite group. The investigations revealed that the traces of volcanic activity have survived in the studied specimens in their structure were the presence of tonstein and inorganic minerals are related to volcanic phenomena. “Floating” in opaque solid–foam resin indicated that resinous substance was strongly heated trough volcanic activity.

Studies of positron annihilation accompanied by EPR technique were undertaken for sodalite and lazurite and their synthetic counterparts (synthetic sodalite and ultramarines). Results of measurements performed by two techniques of positron annihilation spectroscopy (angular correlation of annihilation radiation, ACAR, and positron annihilation lifetime) revealed the undoubted influence of free radicałs on positron annihilation mechanism but both inhibition of positronium formation by them and the effect of filling cages ought to be taken into account. The distinct differences between ACAR curves for sodalites, lazurites and ultramarines probably reflect the presence of different radicals in their cages and chemical heterogeneity as well as the disorder in Al, Si-site ordering in case of ultramarines. Comparison of the results of ACAR measurements with the ones of the EPR studies indicates that there is correspondence between them. Similarly to three families of the ACAR curves, different likes of EPR lines were obtained for three groups of samples; sodalites, lazurites and ultramarines. It is possible that the annihilation of positrons takes place mainly with unpaired electrons recorded by the EPR technique.PACS numbers: 61.90.+d, 71.60.+z, 76.30.-v, 78.70.-g (29) 30 A. Baranowski et al.

No abstract