This paper deals with the effects of modifications to clay-siliceous raw material from Dylągówka (Dynów foothills, SE Poland), which alter the rheological properties of its water suspensions. The investigations were carried out on three samples collected from various depths of the deposit as they considerably differ in their contents of smectite and other minerals. The samples were either modified with soda or activated with sulphuric (VI) acid and used to prepare their water suspensions with various contents of solids. The suspensions were subject to determinations of viscosity and flow curves. Dependencies of three variables of the suspensions (rheological properties, mineral composition of the solid phase, and the modifications introduced) were assessed on the basis of: the contents of the solid phase in the suspensions required to obtain a viscosity of 1000 mPas; hypothetical, calculated thixotropic energy. These show that the amount of solids in the water suspension required to obtain the required viscosity is considerably lower in samples with higher contents of smectite and in those activated with sodium. In turn, the acid activation that partially alters smectite towards a protonated silica gel decreases the viscosity and thixotropy of the suspensions, which was confirmed in the studies of mid-infrared spectroscopy. The conducted studies provide important information needed in designing the mineral composition of drilling fluids and others applications.

Chalcedonite is a diatomaceous sedimentary rock, which, on account of a very small occurrence area, is included into a group of unique rocks. It occurs at Dęborzynka, Gapinin, Lubocz and Teofilów deposits, located on the Rawska Plateau in the region of Tomaszów Mazowiecki and Nowe Miasto. The deposit in Teofilów is the only documented one and it is now being exploited. The surface of this deposit is 577 437 m2 and its geological resources were determined to be 21.587 - 106 kg (21 587.0 thousand tones). The main component of this rock is chalcedon (69.0-96.6 vol.%), however quartz, opal, iron hydroxides, pyrite, manganese compounds and clay minerals occur in small quantities. The active surface of chalcedonite is relatively small and it was determined as 3-6 m2/g. Chalcedonite had a mesoporous structure of a significantly high pore homogeneity, and the total volume of these pores was 0.03-0.04 cm3/g. On account of its small spatial distribution chalcedonite is a unique rock, which has multi-resource properties. It is useful for manufacturing perlite-like material, crystobalite, wollastonite and mullite. It was also found to be a valuable raw material for the production of pastes, scouring powders, grinder tools and also as good filler for the production of : paints, varnishes, enamel ware, lute and putty materials. Because of its mesoporous structure and due to extended outer surface of the grains, chalcedonite is utilized in water treatment technology, mostly as an effective filtration material. A high usefulness of chalcedonite bed for manganese and iron removal from water shows mostly the presence of a low height of iron removal zone in the filter, and it is also manifested by a relatively short time of introduction into effective manganese(II) removal, as well as by good hydraulic properties of the material, which enable to achieve high mass capacities of the filter and to reach long filtration cycles. Chalcedonit is a very good carrier of manganese oxides and its surface modification of leads to the creation of chemically active bed, which enables removal of manganese(II) from water with high efficiency and without the introduction process. Chalcedonite bed effective removes of ammonia nitrogen from the water in the process of nitrification and waste water treatment. Chalcedonite can be also taken into account as a sorbent for the removal of oil spills.