CHEMICAL COMPOSITION AND BULK DENSITY OF MOLDAVITES

The weight, dimensions, bulk density, abundance of bubbles, abundance of lechatelierite, size frequency of lechatelierite and maximum projection sphericity were determined in thirty five moldavites (29 from the Bohemian and 6 from Moravian localities). Fifteen new chemical analyses of Bohemian moldavites are reported. Chemical composition and size frequency of lechatelierite, were the factors determining the bulk density of moldavites. The density decreases with increasing SiO2 content, and with the decrease of Al2O3, Fe2O3 + FeO (and total Fe2O3), Na2O + K2O and, in particular CaO, and with increase of bubbles. The moldavites of the Bohemian and Moravian localities appear to belong to one event. The results obtained support the theory of the impact source area west of Czechoslovakian tektite localities. © 1969.