General information and occurrence
The basic raw materials used for a building ceramics production are various clayey rocks which mixed with water form a plastic mass easy to form and sands so-called “weaken sands” which are added to a clayey raw material to improve the properties of the ceramic mass. The formed and burnt products must be of the appropriate physical and technical features defined by the official standards. Clayey and non-clayey (weaken) raw materials often occur together - in one deposit, in the form of beds or interbeddings, or as the independent accumulations.
The main building ceramic products are: ceramic bricks and breezeblocks, slates, clinker bricks, fittings, ceramic pavements. The raw material from some deposits is being used also for the production of enamel ceramic tiles, stoneware products, ceramic accessories and others.
The raw materials for the building ceramics production owe their yielding features and their ability to be formed to the clayey minerals content. Their content in different rocks varies. In loesses the clayey minerals content is low (couple of %), but in clays it can be up to 100%. Usually in the typical raw materials the content is between 40% and 60%. Other components are mainly the sand and quartzitic dust, feldspars, calcite and dolomite in calcareous raw materials, iron minerals, mica minerals and organic matter. Clayey rocks built of only one mineral occur very seldom, they mostly have several clayey minerals in their composition: kaolin, illite, montmorillonite and chlorites, occurring together in changeable proportions.
Building ceramics raw materials occur commonly in the whole country. They vary in terms of their origin and age. Nowadays, the most important deposits are these of the Quaternary, Neogene, Jurassic and Triassic age. The raw materials of the Quaternary age include mainly stagnant lake sediments such as muds and clays occurring mainly in northern and central Poland. There are also loesses, glacial loams, alluvial loams and loams of weathering covers and sands used. Among older minerals the most important are the Neogene clays of the so-called Poznań Series from south-western and central Poland and maritime Miocene clays occurring in south-eastern Poland in the area of the Carpathian Foredeep. The Jurassic and Triassic deposits are situated at the margin of the Holy Cross Mts., in the Czestochowa region and in the Opole region. The building ceramics raw materials deposits in Poland are presented on the map.
According to the Regulation of the Minister of the Environment of the 1st of July 2015 regarding the geological documentation of a mineral raw material deposit, excluding a hydrocarbons field (number of Polish act: Dz. U. 2015, poz. 987) the limit values of the parameters that define the building ceramics raw materials deposit and its borders (Appendix 8 – table 42) are: - the maximum documentation depth – to the depth of a possible exploitation; - the minimum thickness of the deposit – 2 m; - the maximum overburden/thickness ratio – 0.5; the maximum content of grains bigger than 2 mm – 1%; - the maximum content of a ceramic marl in grains diameter bigger than 0.5 mm – 0.4%; - the shrinkage in drying minimum 6%.
Resources and output
The table given below shows reserves and the state of development and exploration of clay raw material for the building ceramics industry.
The anticipated economic resources of the building ceramics raw materials amounted to 2,033.580 million m3 (about 4,067.158 million tonnes) as of the end of 2020. They decreased by 5.055 million m3 (about 10.110 million tonnes – that is by 0.3%) in comparison with the previous year.
There were 3 new deposits of the building ceramics raw materials documented in 2020: Lublin-Przejrzysta (0.101 million m3) in Lubelskie Voivodeship, Plecewice III (0.133 million m3 of stagnant lake clays, allocated from Plecewice II deposit) in Mazowieckie Voivodeship, Zarzecze-Wojciechowski (0.014 million m3) in Podkarpackie Voivodeship. The documentation of Lublin-Przejrzysta deposit was approved in 2000 (the information and the documentation were submitted to the Polish Geological Institute-National Research Institute in 2021; the exploitation was abandoned probably in 2002), whereas two other documentations were approved in 2020.
For 13 deposits there were new documentations with recalculated resources approved, from which in 4 cases there were decisions of crossing out the deposits from “The balance…” made. The new documentations, updating the boarders and resources, were elaborated for the following deposits: Bolków I (0.000 million m3; due to the concession extinction) in Dolnośląskie Voivodeship, Gozdnica (deposit boarders extension – the anticipated sub-economic resources documented equal 0.249 million m3) in Lubuskie Voivodeship, Budy Mszczonowskie III (-0.024 million m3), Marki-Pole Południowe (-0.011 million m3; residential housing planned in the deposit area) and Konstantynów (-0.074 million m3; the updating after the allocation of Barcik 10 deposit area in 2014) in Mazowieckie Voivodeship, Paczków (+2.447 million m3; deposit area enlarged to the depth of 30 meters and by the areas adjacent from south-east) in Opolskie Voivodeship, Rozpędziny (-0.615 million m3; within the deposit boarders the sand resources remained, whereas the Neogene clays were crossed out from “The balance…”) in Pomorskie Voivodeship, Witaszyce (-0.687 million m3; the anticipated sub-economic resources where allocated from the deposit) in Wielkopolskie Voivodeship, Gnaszyn Północ (resources covered by a detailed exploration – reclassified from C2 to C1 category) in Śląskie Voivodeship.
There were following deposits crossed out from “The balance…”: Bojanówka Zachód (-0.030 million m3) in Lubelskie Voivodeship, Gorzów Wielkopolski (-0.472 million m3) in Lubuskie Voivodeship, Konstancja-Mieszczańska (-2.521 million m3) in Małopolskie Voivodeship, Pniów-Bałdos I (0.000 million m3) in Podkarpackie Voivodeship and Bielszowice II (-0.218 million m3) in Śląskie Voivodeship. The total resources drop amounted to 4.241 million m3.
Out of 1,127 documented deposits of the building ceramics raw materials, exploited deposits (130) account for 11.5% (including: 7.2% deposits exploited continuously (81) and 4.3% deposits exploited temporarily - 81), non-exploited deposits (301) account for 26.7% (including: 20.1% deposits covered by a detailed exploration (227) and 6.6% deposits covered by a preliminary exploration - 74) and abandoned deposits (696) account for 61.8%.
Similarly, out of the total amount of the anticipated economic resources (2,033.58 million m3): the resources within exploited deposits (255.31 million m3) account for 12.6% (including: 10.4% deposits exploited continuously (212.06 million m3) and 2.1% deposits exploited temporarily – 43.25 million m3), the resources within non-exploited deposits (1,443.81 million m3) account for 71.0% (including: 11.3% in the deposits covered by a detailed exploration (230.27 million m3) and 59.7% in the deposits covered by a preliminary exploration – 1,213.54 million m3) and the resources within abandoned deposits (334.47 million m3) account for 16.4%.
Resources documented in A+B and C1 categories (the detailed exploration) account for 34.5% of total anticipated economic resources. The remaining part of resources is documented in C2 or D categories (the preliminary exploration). More than a half of resources covered by the preliminary exploration (60%) are resources documented within the overburden of non-exploited brown coal deposit Legnica-pole Wschodnie (727.65 million m3 of clays documented in C2 category).
The economic resources were documented for 72 deposits and amount to 151.796 million m3 (about 303.592 million tonnes) that accounts for 59.7% of the anticipated economic resources of these deposits. The economic resources in 2020 decreased by 2.430 million m3 (1.6%) in comparison with the previous year. The was mainly the result of the exploitation. Moreover, there were economic resources updated for: Rudak 1 deposit in Kujawsko-Pomorskie Voivodeship (-0.854 million m3), Gozdnica deposit in Lubuskie Voivodeship (+0.250 million m3), Kolbuszowa-Kupno in Podkarpackie Voivodeship (+0.872 million m3); there were the economic resources crossed out from “The balance…” from: Krzyż deposit in Małopolskie Voivodeship (-0.698 million m3) and Bojanice deposit in Wielkopolskie Voivodeship (-0.332 million m3) as the result of the mining areas extinction (the exploitation concessions extinction).
In 2020, the output of the building ceramics clays was equal 1.565 million m3 (about 3.130 million tonnes) and decreased in comparison with 2019 by 0.233 million m3 (13.0%). The exploitation was being carried out from 81 deposits.
Considering particular Voivodeships, the output was as follows (in a descending sequence): in Świętokrzyskie Voivodeship 0.334 million m3 (21.4% of the domestic output); in Małopolskie Voivodeship 0.199 million m3 (12.7%); in Śląskie Voivodeship 0.187 million m3 (11.9%); in Dolnośląskie Voivodeship 0.174 million m3 (11.1%); in Podkarpackie Voivodeship 0.114 million m3 (7.3%), in Pomorskie Voivodeship 0.088 million m3 (5.6%); in Opolskie Voivodeship 0.086 million m3 (5.5%); in Mazowieckie Voivodeship 0.080 million m3 (5.1%); in Wielkopolskie Voivodeship 0.078 million m3 (5.0%); in Lubelskie Voivodeship 0.062 million m3 (4.0%); in Zachodniopomorskie Voivodeship 0.044 million m3 (2.8%); in Lubuskie Voivodeship 0.039 million m3 (2.5%); in Kujawsko-Pomorskie Voivodeship 0.035 million m3 (2.2%); in Łódzkie Voivodeship 0.025 million m3 (1.6%); in Podlaskie Voivodeship 0.010 million m3 (0.7%); in Warmińsko-Mazurskie Voivodeship 0.010 million m3 (0.6%).
The figure given below shows changes in the domestic resources and production of the clay raw material for the building ceramics industry in Poland in the years 1989-2020.
In The balance of prospective mineral resources of Poland, the prognostic resources (category D1) of the building ceramics raw materials were assessed to be equal 1,328 billion m3 within 65 areas, moreover there were 267 prospective areas described (category D2 without the resources assessment)*. The majority of the prognostic resources is formed by the Neogene clays of the Poznań series (45.7% of the prognostic resources, from which 20% are the clays accompanying the brown coal deposits), the Miocene marine clays (33.3%), the stagnant clays (18.3%) and other (2.7%). The geographical distribution of the resources is uneven: in Dolnośląskie Voivodeship there is 43.1% of the resources located, in Podkarpackie Voivodeship 28.2%, in Podlaskie Voivodeship 9.2%, in Warmińsko-Mazurskie Voivodeship 5.1%, in Śląskie, Pomorskie, Świętokrzyskie and Małopolskie Voivodeships – from 2% to 3%, and in the remaining Voivodeships – 6.2% in total. Except for the determined areas, there are also other possibilities for the valuable clayey raw materials discovery.