Szakáll Sándor - Jánosi Melinda: Minerals of Hungary (Topographia Mineralogica Hungariae 4. Miskolc, 1996)

So-called 'friable' dolomite has a somewhat different mineral association of kaolinite, halloysite, hexahydrite, and vaterite. In some of these quarries, concretions can be seen, built up from mm size grains of dolomite and calcite cemented together. Cretaceous alkaline basic rocks are associated with these Triassic limestones and at their contact, a zone of varied, but hitherto, little studied minerals exists. Fig. 50 CALCITE (1

1 cm sp) Fig. 51 META CINNABAR (0.3 mm xl) Pilisjászfalu Budapest The sedimentary rocks of the Eocene and Oligocène (limestones, marls, and sandstones) are in many respects very similar to the Triassic sedimentary rocks, as are their fracture-filling mineral assemblages of hydrothermal origin of calcite, some barite and goethite, SO