Although there is an extensive literature on the amphiboles, especially those of the monoclinie series, there appear to be only few records for basaltic hornblendes in which the physical properties and the chemical composition have been determined in detail on the same sample of material, Mention may be made of the later papers by S. L. Penfield and F. C. Stanley, S. Kreutz, W. E. Ford, and H. Küchler. The basaltic hornblende described in the present paper is found in the volcanic tuff-breceias

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... of Pliocene age in the neighbourhood of Lake Balaton. The locality is near the small village of Balatonesicso on the southern slope of the 'Fenyves' hill, the top of which is capped with basalt. Tile hornblende is found as loose crystals in the tuff-breccia and also in blocks rich in olivine. Specimens of some size, up to 2 or 3 cm. in length, may be collected.