Syderyt magnezowy (syderoplezyt) z utworów westfalskich Lubelskiego Zagłębia Węglowego

Abstract

MAGNEZIUM SIDERITE (SIDEROPLESITE) IN WESTPHALIAN FORMATIONS OF THE LUBLIN COAL BASIN Summary Investigation of carbonate rock from a bore hole situated near Łęczna, Lublin Coal Basin, has proved that the rock is magnesian siderite (sideroplesite), a member of the isomorphous series siderite - magnesite. It contains 31,46% Fe and 8,14% MgO (Tab. I). Interplanar spacings and unit cell edges of this rock are intermediate between those of siderite and magnesite (Tabs. IV and V). The infra-red absorption bands of this mineral are distinctly shifted towards the higher wave numbers, as compared with those of pure siderite (Tab. III). Shape of DTA curve seems to yield an additional evidence of diadochic replacement of Fe2+ by Mg2+ in the siderite lattice.