Mookaite石——西澳大利亚的装饰石

Mookaite石是一种吸引人的多色装饰石,产于西澳大利亚Kennedy山脉西缘Gascoyne河以北的少数地方。从岩石学上,Mookaite石由Windalia放射虫岩层的硅化放射虫岩构成,该岩层为Carnarvon大盆地沉积序列的一部分。硅化作用形成瓷状岩后,Fe染色导致其具有引人瞩目的黄色、红色、紫色和棕色图形。瓷状岩细粒,坚硬,无定向性,抛光性极好,在世界范围内广受欢迎。     

Geochemical analysis of radiolarite samples from the Carpathian basin

A very important raw material of the prehistoric age, radiolarite was investigated in this work. Samples from geological and archaeological sites of the Carpathian basin, Greece and Austria were analyzed by ion beam methods, namely proton-induced gamma-ray emission (PIGE) and proton-induced X-ray emission (PIXE) techniques. Our aim was to study to what extent we are able to classify the specimens with various macroscopical features and different source areas. In order to answer this question, a cluster analysis was carried out on the concentration data set deduced from the analysis. Correlations between the elemental compositions and the source regions are established.