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

concentration was found adjacent to quartzite veins drilled at Retez shaft, near Velence, appearing in handsome foliated stacks, but reserves were in-sufficient for industrial purposes. In the contact zone between granite and the argillaceous slate encircling the granite, slender prisms or needles of tourmaline were encountered in quartz veins in some of the quarries together with traces of tungsten mineralisation. A little further West of the mountains, Paleozoic sedimentary rocks occur on Szár Hill, at Polgárdi, fractures in which are filled with delicate crystals of calcite. Fig. 59 THA UMASITE (0.2 mm xl) Fig. 60 OKENITE (2 mm sph) Polgárdi Polgárdi In the mountains and close by, near the surface, small patches of Eocene andésite occur which contain a complicated hydrothermal as-