Dr. Nagy I. Zoltán szerk.: Fragmenta Mineralogica Et Palaentologica 3. 1972. (Budapest, 1972)

Fragm. Min. Pal. 3. 1972. A study of lamprophyric dike rocks of the Velence Hills (Hungary) by A. Embey-Isztin Hungarian Natural History Museum Mineralogical-Petrological Department, Budapest Introduction The granite massif of the Velence Fills is poor in dikes of basic character. Their occurrence is known at three places only, whereas granite porphyry and quartz dikes especially aplite dikes are numerous in the Velence granite

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. 1.). Several authors dealt with the geology and petrology of the Velence Hills, among them works of Vendl (1914), Jantsky (1957), Gokhale (1965) and Buda (1969) being the most important. A. Vendl (1914) described three kersantite dikes, two of them occur southeast of the top of the Sárhegy, in a distance of a few meters from each other, the third one is at the east edge of the Csala Forest. According to him the following minerals are present in the dike rocks: plagioclase, orthoclase, quartz, hornblende, biotite, apatite, zircon and magnetite. Besides he claims that the double-dike of Sárhegy and the Csala Forest dike are uniform, both of mineralogical and petrological point of view, only hornblende is less abundant and biotite is more abundant in the latter. On the basis of the dominant hypothesis of his age he regarded these formations as diaschistic dikes. M. Vendl (1923) described a weathered rock from the Székesfehérvár Quarry as a spessartite. According to her the rock is composed of plagioclase, hornblende, augite and magnetite. The