The work concerned the effects of the thermal treatment of diatomites from the Jawornik deposit (an example of the diatomites of the Leszczawka Member of the Polish Outer Carpathians). Five distinct lithological varieties were subjected to calcination at 600°C in ambient air.The thermal impact induced the following changes to the rocks. Their overall rock porosity increased, most distinctly in the initially softer varieties, and the internal pores of the siliceous frustules themselves usually became larger due to the initial melting of the silica phases. Most of the diatoms, quartz and feldspars cracked as a result of their brittle fracturing under compressive strain resulting from substantial and differing size changes of growing grains. Clay minerals were thermally transferred, changing their volume. The organic matter dispersed through-out the diatomites was partly oxidized and removed. At the same time, the structure of the rocks was strengthened, as confirmed by an increase in their microhardness. The microhardness of soft and porous diatomite varieties increased considerably on heating, but that of the hard and compact variety changed to a smaller degree. The increase is directly related to the content of the clay minerals. The impact of other mineral components was not detected. The calcination of lithologically diversified diatomites provided the mineral with raw material with deicing and antisliding properties. The technology of its production has been determined by the authors and submitted as a patent.

Streszczenie: Przedstawiono stan kopalń na tle tradycji wydobycia i użytkowania surowców kamiennych. Wytypowano czynne kamieniołomy, w których tradycyjnie pozyskiwane były bloki, jak też i takie, w których z racji wykształcenia serii złożowych, bloki mogą być przedmiotem eksploatacji w przyszłości. Oceniono też złoża, w których niegdyś wydobywano materiały kamienne powszechnie stosowane jako materiały dekoracyjne w krajowej architekturze, mimo że aktualnie są one nieczynne. W sumie przeanalizowano ponad 230 złóż. Zaprezentowano, uzasadnione ekonomicznie, perspektywy rozwoju wydobycia materiałów dekoracyjnych i architektonicznych w Polsce południowo-wschodniej na tle wymagań rynku europejskiego i możliwości wynikających zarówno z ograniczeń środowiskowych, jak i zasobowych. Ustalono, że są one zróżnicowane w zależności od walorów dekoracyjnych poszczególnych skał, ich bloczności i wielkości zasobów. Wydzielono skały i złoża, które mają możliwości rozwoju wydobycia na skalę europejską, krajową i lokalną. Pierwsze to zlepieńce zygmuntowskie, wapienie morawickie i zalesiackie oraz dolomity diploporowe. Zakres krajowy mogą mieć odpowiednio zagospodarowane złoża paleozoicznych wapieni okolic Kielc i Krzeszowic oraz niektóre bloczne złoża piaskowców z obrzeżenia Gór Świętokrzyskich i Karpat. Rozwój na skalę lokalną mają zapewnione drobne złoża piaskowców w obrzeżeniu Gór Świętokrzyskich i z Karpat oraz wapieni na Jurze Krakowsko-Częstochowskiej, produkujące materiał wykorzystywany w małej architekturze. Wykazano zagrożenie dla złóż skał blocznych, związane ze stosowaniem materiałów wybuchowych przy wykorzystaniu ich zasobów do produkcji kruszyw łamanych. Dla złóż najbardziej atrakcyjnych skał uzasadniono konieczność ich ochrony przed eksploatacją w innych celach niż produkcja bloków. Stwierdzono, że powrót do zarzuconych kamieniarskich tradycji jest możliwy i konieczny z racji licznych powiązań, poprzez historię, architekturę i sztukę, z kulturą narodową. Wymaga on sporych inwestycji dla unowocześnienia sposobu zagospodarowania złóż, a także związanych z promocją polskich kamieni na rynku europejskim. Należy przy tym uwzględnić możliwość zaangażowania funduszy Unii Europejskiej.

The sandstones with a laminated structure are common building materials. Lamination is macroscopically expressed as colour and grain size variations observed both in the deposit and within individual beds; therefore, the properties of such sandstones are diverse depending on the spatial distribution of the binding mass and framework components. For the terrestrial sandstones of different genesis, four types of laminae have been distinguished based on petrographic studies. They have a siliceous binder or a mixed ferruginous–siliceous–argillaceous binder with different proportions of these components. In laminae of types I–III, the grain framework is built mainly of quartz grains, and in type IV, it is accompanied by numerous lithoclasts and feldspars. Knoop hardness and CERCHAR abrasivity were tested in each lamina variety, and the results were correlated with the equivalent quartz content and the longitudinal ultrasonic wave velocity measured perpendicular and parallel to the lamination. The proposed research methodology was not used in previous studies on terrestrial laminated sandstones. The results explain a strong dependence between mineral composition, structure of laminae, and technical parameters of rocks. The knowledge of this relationship facilitates the selection of rocks that meet the relevant technical requirements and helps to optimally manage the resources of sandstone deposits.

This work is an attempt to determine the scale of threats to the mineral security of Poland in the area of non-energy raw materials resulting from Russia’s invasion of Ukraine. In particular, it aims to identify those industries whose proper functioning may be threatened in the face of the limited supply of raw materials from three directions – Russia, Belarus and Ukraine. An element of the analysis was also the indication of possible alternative sources of the supply of these raw materials. For this purpose, the directions of imports to Poland of about 140 non-energy raw materials in 2011–2020 were analyzed. As a result, about thirty raw materials were selected, the supplies of which came from, among others, at least one of the three mentioned countries. To determine the raw materials for which the disruption of supplies may have the most serious impact on the functioning of the Polish economy, the following criteria were adopted: a minimum 20% share of these countries in covering the domestic demand in 2020, and a minimum value of these imports in 2020 of 20 million PLN. These threshold conditions were met by eight raw materials: iron ores and concentrates, carbon black, potash, aluminum, ferroalloys, nickel, ball clays and refractory clays, and synthetic corundum. Among these, the need to change the directions of supplies applies to the greatest extent to iron ores and concentrates, aluminum and nickel, while in the case of non-metallic raw materials, it applies most to ball clays and refractory clays and potassium salts. These are among the most important raw materials necessary for the proper functioning of the national economy, but their shortage or disruptions in the continuity of their supplies pose a real threat to the mineral security of Poland.

Diatomite rocks from the eastern part of the Polish outer Carpathians come in several varieties with different colour, compactness, amount of clay and sandy substance as well as the degree of silicification. One of them is dark grey blocky diatomite, present in the Jawornik deposit and characterised by average quality. During the tests, it was thermally calcined at temperatures from 300°C to 1,200°C in order to improve its functional properties. The results of observations regarding the changes that the rock and its components underwent under conditions of increasing temperature were presented. The results of thermal analysis, X-ray diffraction and tests of physical properties (i.e. density, water absorption and Vickers microhardness) of the rock were presented. Detailed observations of the rock’s mineral components were made using a scanning microscope. Their physical changes (e.g. cracks or signs of melting) and chemical transformations were described. It has been shown that during calcination, irreversible changes occur in the mineral composition and structure of diatomite. It was proven that for the discussed diatomite the optimal calcination temperature is 900°C, as it ensures the greatest increase in its open porosity by 11% and an almost threefold increase in its hardness. The chemical composition of diatomite also changes due to the combustion of the organic matter present in it and the resulting relative increase in the 1,200 content. Calcination improves the technological features of this variety of diatomite, making it similar to the best quality varieties found in this deposit.

A lithological profile and measurements of the orientation and spacings of natural discontinuity planes were carried out in the Górka-Mucharz sandstone excavation (Krosno Beds, Outer Carpathians, Poland). In addition, the density of the discontinuities was assessed by measuring their spacings using oriented digital photographs of the quarry walls. An orthophotomap was also used in assessing the orientation and density of fractures with the tools available in QGIS. It was shown that digital image analysis can be used as an alternative to direct field measurements, especially in situations where access to an outcrop is difficult. The distributions of spacings larger than 40 cm, obtained by direct measurements and based on digital images of the quarry, were comparable. As a consequence, both measurement techniques yielded similar values of the quantity of blocks (QB), which differed by less than 2% for the minimum block volume in the range 0.4-1.0 m 3 and by 6-7% for larger blocks. On the other hand, measurements of discontinuity spacings that were taken on the basis of an orthophotomap can only serve to estimate the approximate maximum value of this parameter. However, the use of orthophotomaps gives a more explicit spatial pattern of the main vertical joint sets than direct measurements in the quarry. The analysis results also showed the following: (i) the presence of tectonic disturbances visible at the highest level of the deposit; (ii) higher density of set A fractures with planes deepening in the NE direction and a considerable reduction of the QB parameter, particularly in the peripheral NE and SW parts of the deposit; (iii) differences in the orientation of the discontinuity system between particular beds. The variable density of the discontinuities in the excavation is related to the presence of the faults that limit the Górka-Mucharz deposit.