Kryteria hydrotermalnego pochodzenia minerałów w ujęciu S. J. Thugutta

Abstract

The criteria of hydrothermal origin of minerals as conceived by S. J. Thugutt Profesor S. J. Thugutt w pracach nad hydrogenezą minerałów zdołał wykazać: po pierwsze tworzenie się wodnych roztworów koloidalnych minerałów uchodzących praktycznie za nierozpuszczalne w wodzie, po drugie — anormalny skład chemiczny skaleni alkalicznych powstających z takich roztworów i po trzecie wykazał obecność pozostałości fazy rozproszonej, uw idoczniającej się w badaniach ultramikroskopowych w minerałach wodnego pochodzenia, co jednocześnie tłumaczy wielobarwność tych minerałów. In the scientific work of Stanisław Józef Thugutt, the late Professor and Director of the Department of Mineralogy at the Warsaw University and the first and last Director of the Laboratory of Mineralogy of the Warsaw Society of Science and Letters (Warszawskie Towarzystwo Naukowe) an eminent place is held by the problem of the hydrothermal origin of many minerals. In his experiments on the solubility of minerals S. J. Thugutt succeeded in demonstrating that practically no minerals can withstand the dissolving action of water, if only proper conditions of temperature, pressure and time are ensured. He obtained solutions, mostly colloidal, of many minerals hitherto considered as insoluble in water. These results provided a satisfactory explanation of the way different mineral substances can circulate in rock fissures and engender secondary minerals in the form of either crystals or amorphous botryoidal forms or else pseudomorphoses filling up the places occupied formerly by other minerals. He also emphasized the fact that sodium and potassium feldspars formed in this way show an anomaly in chemical composition consisting in a deficit in silica in relation to alumina, which is the conr sequence of hydrolysis and a partial removal of silica in the course of this process. S. J. Thugutt also demonstrated that minerals of hydrothermal origin can be distinguished by way of ultramicroscopic investigations from those of igneous origin, as in the former remnants of the colloid phase can be traced which is never the case with the latter. He explains the fact that a great number of minerals of hydrothermal origin are multicoloured by the presence of colloid particles of various degrees of dispersion.